Growing
These Are The Benefits Of Loam-Based Compost (And How You Can Make Your Own)
IN THIS GUIDE What Is Loam-Based Compost? What Is It Made Of? What Are Its Benefits? How To Make Loam-Based Compost What Plants Is Loam-Based Compost Good For? When To Avoid Using It References John Innes composts are popular here in the UK, and in other countries. What Is Loam-Based Compost? A loam-based compost is a compost that contains a certain proportion of loam soil. Most potting composts do not contain any soil at all. But there are some – most notably the John Innes composts, that do have some ‘soil’ in their composition. It is worth noting that the common John Innes loam-based composts contain soil ingredients that are not necessarily loam in their modern formulations. Loam is the name given to soils that are balanced mixtures of mineral components of different sizes: clay, sand and silt. They also have an organic matter component. These soils are the best soils for gardeners. They combine the best qualities of different soil types and are great for plant growth. The loam in loam-based composts is sterilised to get rid of weeds, pests and diseases. This means that the gardener should encounter fewer problems than they would with a non-sterilized soil-based growing medium. There are several different common John Innes composts, or potting media that are on the market today. These are: John Innes Seed Compost – for seeds and cuttings John Innes Potting Composts (Soil Mix and Fertiliser Base) – best for established plants and general use John Innes Compost No. 1 – for seedlings and cuttings John Innes Compost No. 2 – for transplanting young plants or plants that don’t thrive in rich soil like thyme John Innes Compost No. 3 – for established plants John Innes Ericaceous Compost – for acid-loving plants There are also peat-based and peat-free composts/ growing media with ‘added John Innes’. “I strongly suggest trying the peat-free mixes of John Innes,” says Horticulturist Dan Ori, “they perform well and manufacturers are not having to harvest from peat bogs to make them. “It will take a little adjustment to understand when to water, as it is different to compost containing peat; if you use a moisture meter to help you judge when to water, you will find it an easy transition.” Read on to learn what exactly goes into each of these different soil-based growing media mixes. What Is It Made Of? The various types of loam-based John Innes compost have different ingredients and contain materials in differing quantities. Here are some details to help you understand what is in John Innes loam-based composts, and how to make these products yourself following their recipes.1 John Innes Seed Compost is used for sowing seeds, and for cuttings, and seedlings can be grown on in it until they are ready for pricking out. It comprises: 2 parts loose bulk medium sterilized loam. 1 part peat or peat substitute. (Peat is often replaced with other materials and this is a more eco-friendly choice.) 1 part coarse horticultural sand. John Innes soil mix is: 7 parts sterilized loam. 3 parts peat or peat substitute. 2 parts loose sand. And John Innes fertiliser mix (also known as John Innes base) is: 2 parts by weight of hoof and horn meal. 2 parts by weight of superphosphate. 1 part by weight of sulphate of potash. John Innes Compost No.2 is used to grow many houseplants, and vegetable plants in containers. For each 2 gallon bucket of soil mix, add 56g of fertiliser mix, and 10g ground chalk. John Innes Compost No.3 has even more nutrients. It is used for established trees, shrubs and other mature plants, and mature indoors plants that will remain in their containers for a long time. This mix is also good for particularly ‘hungry’ plants like tomatoes, for example. Add 84g of fertiliser mix and 15g of ground chalk. What Are Its Benefits? Loam based composts can be beneficial because the loam helps to avoid fluctuations in water and nutrient content in the growing medium. Since the soil part of the media is very stable, this can be especially useful in situations where plants are placed for the long term. How To Make Loam-Based Compost It is important to note that you can make your own loam-based compost mixes at home. And you do not necessarily have to stick to, or remain close to, the formulations described above. One option if you have a good quality loam soil in your garden is simply to use some of that. You can also make a good loam by stacking turfs of grass upside down until it breaks down. As mentioned above, all commercial loam-based composts use sterilised loam. The sterilisation process is undertaken because soil or loam that has not been sterilised can contain weeds, pests and diseases. It is not especially easy to sterilise loam at home, but it is possible to do so in your oven. Personally, I use a mix of 1/3 loam (from the garden), 1/3 homemade compost (with well-rotted manure and bedding from our chickens) and 1/3 leaf mould (from autumn leaves) to make a mix that works well for mulching around vegetables and placing in containers. I do not bother with sterilisation and while there will be the odd weed here and there, and the odd problem, these are not too much of an issue in my organic garden. What Plants Is Loam-Based Compost Good For? A loam-based compost can be good for a wide range of different plants. The right loam-based formulation can be used at all stages of plant growth. But it is important to remember that there are certain plants that need a different formulation, that is more free draining or which contains a specific mix of nutrients. Loam based composts are generally excellent for the vegetable garden, and for mature plants that will remain in place for longer periods of time. They can be used for indoors or outdoors container gardens. And can often be the best choices when plants are not grown in contact with the natural soil. When To Avoid Using It Commercial composts of this type, either John Innes composts, or composts with ‘added John Innes’ should have been specially formulated to allow for good drainage, aeration, fertility and optimal plant health and plant growth. It is always important to note that as with other composts, the quality of these commercial composts can vary considerably. Some are much better than others. The texture of store-bought compost with loam will vary considerably depending on the exact composition of the loam and where the material came from. Those who are trying to avoid harmful practices and want to garden as sustainably as possible should aim to avoid choosing products that contain peat, non-sustainably sourced loam, and any non-organic fertilisers or other problematic ingredients. If possible, in order to make your gardening efforts as sustainable as possible, you should try to take a DIY approach, using materials sourced from your own home and garden, or as locally as possible. References 1. John Innes potting compost. (n.d.). Royal Horticultural Society. Retrieved March 20, 2023, from https://www.rhs.org.uk/soil-composts-mulches/john-innes-compost
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All (General) Purpose Compost - What Is It Made Of And When Should You Use It?
IN THIS GUIDE What Is All Purpose Compost? Considerations What Is It Made Of? What Are Its Benefits? How To Use General Purpose Compost What Plants Is All-Purpose Compost Good For? When To Avoid Using It Frequently Asked Questions References When people talk about a multi-purpose or ‘all-purpose’ compost, they are usually referring to commercial composts that you can use in your garden in a range of different ways. These commercial composts are specially formulated with a range of different ingredients. What Is All Purpose Compost? All-purpose compost is a multi-purpose compost that will suit a wide range of applications in your garden. They can provide nutrients, and the right growing environment for a wide range of plants, at all stages of their growth, right through from seed sowing to maturity. All-purpose composts can be used as mulch to enrich beds, borders and other growing areas. They can also be suitable for filling planters, containers and pots for houseplants and for an outdoors container garden. Considerations Since all-purpose composts are ostensibly formulated for use in a huge range of different ways, this means that they can often be a good choice for new gardeners. It is important to understand, however, that all-purpose composts vary significantly in quality. While these composts can often be cheaper than other more specific use composts, results can be variable. Even bags of compost from the same company have been found to vary significantly in quality. It is also important to recognise that all-purpose composts can vary in how eco-friendly and sustainable they are. Their credentials can vary quite considerably in this regard depending on what ingredients are mixed into them. What Is It Made Of? A general-purpose compost is made from biodegraded (or rather partially biodegraded) organic material. But which materials went into making the compost will depend on the formulation of the commercial compost you choose (or what you put into your composting system if you made it yourself). Many all-purpose compost brands contain peat. But there are other peat-free alternatives to consider, and you should do so. Peat free multi-purpose composts can be wood-based, wool-based, or coir based, for example. Commercial brands of all-purpose compost often also include other ingredients intended to promote healthy and strong root formation and plant growth. For example, all purpose compost often includes materials designed to help in aeration, such as vermiculite or perlite. Vermiculite is a light, spongy material which is a naturally occurring mineral resembling mica, and holds more water and nutrients as well as aerating the mix.1 Perlite is expanded volcanic glass and gives a compost that is more free-draining. Though these can be helpful for gardeners, it is worth noting that neither is a particularly eco-friendly option. Some all-purpose or multi-purpose compost brands will also incorporate some controlled-release synthetic fertiliser capsules that will slowly release nutrients over a matter of weeks or months. If you wish to garden organically then these are, of course, options that should be avoided. What Are Its Benefits? A good quality all-purpose compost is usually the cheapest sort of compost that you can get. Short of creating your own compost at home, of course, this is the most affordable option. This also makes things easy for new gardeners, as they do not have to think too deeply about which compost they need for specific uses in their gardens or containers. How To Use General Purpose Compost As mentioned above, general-purpose compost can be used for a range of different garden applications. Also, the nutrient composition of different all-purpose composts can vary significantly. In general, a good all-purpose compost is great for: Topping new raised beds or growing areas (for example, those made with the no dig lasagna method) in your garden. Mulching existing beds, borders or growing areas to replenish fertility and protect and improve the soil. Filling containers for a range of indoors and outdoors grown plants (any that do not have more specific needs when it comes to their growing medium). What Plants Is All-Purpose Compost Good For? An all-purpose compost is good for placing as a mulch, or using as a growing medium for mature plants (some are also fine for seed sowing, seedlings and cuttings, though this depends on the particular brand and its formulation). It can be very useful in growing a wide range of plants, including many fruits and vegetables in a food-producing garden, shrubs, trees, bedding plants and herbaceous perennials. When To Avoid Using It Avoid using an all-purpose compost for plants that have more specific requirements when it comes to their growing medium. For example, some plants are ericaceous and require an acidic compost growing medium or mulch. Others require better drainage than a typical all-purpose compost provides. We recommend that you avoid purchasing all-purpose composts that contain peat, due to environmental concerns.2 We also suggest that you look into making your own, so you can significantly reduce the amount of multi-purpose compost you must buy in future. Frequently Asked Questions Can You Use All Purpose Compost For Acidic Loving Plants? Whether you bought it or made it yourself, the pH level of an all purpose compost can vary quite a lot. Usually, it is neutral to mildly acidic. It will have been formulated to be suitable for as wide a range of plants as possible. However, because it has been formulated to suit many plants, it will not be suitable for some – including plants that like acidic growing conditions. For plants that require acidic conditions like, for example, azaleas, many heathers, acers, blueberries, etc. you should use an ericaceous compost. This is an acidic compost that has been formulated to provide growing conditions with a lower (more acidic) pH. Ericaceous compost that you either buy or make yourself will be a better choice for growing these plants in containers, or for using as mulch around them. How Long Does All-Purpose Compost Last? How long all purpose compost will last before it is used depends to a large degree on how it is stored. If it is kept dry, and in a sealed container, then it should last indefinitely. On the other hand, if the container is breached, or the compost is on the soil or open to rainfall, the nutrients within it will slowly start to leach out and the materials will continue to break down. The compost will usually have depleted to the point where it is no longer ideal for plant growth within a few months. If you have used an all-purpose compost in containers, you should note that you’ll need to replenish the nutrients in it over the growing season to encourage plants to continue to grow strong. To give plants a boost, you can top-dress or mulch around the tops of the containers with organic matter/soil enriching materials. And you can use organic liquid plant feeds to give plants nutrients more quickly. With many plants, you should plan to replace the growing medium in the pots every 2-3 years. If you are mulching around plants in your garden, compost is great as a slow-release fertiliser and will also improve the soil. Micro-organisms will feed off organic matter in the compost that has not yet fully decomposed, and soil biota will help incorporate the compost and its nutrients into the soil below. You should plan on replenishing the growing areas with compost or other fertilisers/soil amendments at least once a year. Should You Use This Compost Type For Indoor Plants? All-purpose compost is fine for many houseplants. But certain groups of plants, like orchids, bromeliads, succulents and cacti will require more specific compost mixes and will not thrive in an all-purpose compost. Can I Use All-Purpose Compost For Seeds? Some general-purpose composts will be fine for seed sowing, seedlings and cuttings. Others, however, may not be the best choice for these stages of plant growth. What it comes down to is the texture of the compost, and how fine-grained it is. If it is relatively fine-grained, it will often be suitable for seed starting. Remember, seeds need water, oxygen and the right temperatures for germination, but they do not yet need to take in nutrients from the soil. This means that special seed composts are sometimes used, which tend to be low in added nutrients, yet have a texture that helps seeds and young seedlings. One benefit of using a more general compost (either an all-purpose compost you have bought which has a fine enough texture, or a compost/ potting mix you have made yourself at home) is that the seeds can be left to grow on in this medium. So ultimately they don’t necessarily have to be moved to different containers filled with a different growing medium for the next stage of their growth. Do Mice Eat Multi-Purpose Compost? Mice will not eat a potting mix or compost itself, unless it is a poor mix with non-decomposed organic material. However, they may enjoy the friable texture of the mix and use it to hide within, and as a place to store bits of found food. References 1. What Is Vermiculite? (n.d.). The Vermiculite Association. Retrieved March 28, 2023, from https://www.vermiculite.org/blog/horticulture/what-is-vermiculite 2. Sams, C. (2021, August 27). Gardeners should end their love affair with peat. The Guardian. Retrieved March 10, 2023, from https://www.theguardian.com/environment/green-living-blog/2012/apr/05/gardeners-peat-carbon
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These Sunflower Care Guidelines Will Help Keep Your Plant Stems Strong
IN THIS GUIDE Overview Why Grow Sunflowers? How To Grow Sunflowers Sunflower Plant Care Common Problems References Sunflowers are great for novices and experienced gardeners alike, and can find a place in many gardens. Kids will love learning to grow them with you, and as an easy plant to grow, they can be your gateway to growing your own – no matter how green-fingered you may be. You might think you know these familiar flowers well, but they can be surprising. Overview Botanical Name Helianthus annuus Common Name(s) Sunflower Plant Type Annual Flower Native Area Americas Hardiness Rating H4 Foliage Broad, oval to heart-shaped, rough hairy leaves Flowers Huge flowers up to 30cm across with bright yellow petals When To Sow April, May Flowering Months June, July, August The common sunflower, Helianthus annuus, is a tall and fast-growing annual. In summer, of course, the plant bears huge flowers up to 30cm across, with bright yellow petals and large brownish centres. Heliotropism One fascinating thing about sunflowers is that they offer an example of a natural phenomenon known as ‘Heliotropism’. While the flower heads are young, the flowers generally tend to turn to follow the sun across the sky as it travels from east to west. Researchers have come to the conclusion that sunflowers show this specific type of heliotropism because their stems elongate at different rates on each side at different times of the day.1 This ‘solar tracking’ can be a fascinating natural phenomenon to witness when growing sunflowers in your own garden. It is thought that facing the sun during the day in the early stages of growth brings benefits for these plants. Not only does it maximise photosynthesis, it also increases warming of the flower on each plant, thereby attracting more insects for pollination. Researchers at the University of Virginia found that east-facing mature sunflower blooms drew five times the number of pollinating insects when compared to west-facing ones.2 Why Grow Sunflowers? Sunflowers are great plants to grow for a great many reasons. Easy To Grow For one thing, they are a fantastic choice because they are very easy to grow. The seeds are large and easy to handle, and the plants germinate and grow quickly so you do not have to wait around too long to see impressive results. Visual Appeal Sunflowers look beautiful and very impressive, with their enormous heads; planting just a few can have a big impact on the visual appeal in a garden. Another thing to consider is that the structure of the sunflowers, which grow heads and shoulders above many other flowering plants, means they can add height and structure to a bed or border. Companion Benefits Sunflowers are great mixed in with other flowering plants in an ornamental border, but they can also work well as companion plants in a kitchen garden. Not only do these flowers attract plenty of pollinators to your garden while they are in bloom, they also attract predatory insects like lacewings and parasitic wasps that help keep pest numbers down. They can also serve as structure for climbing edibles like beans to grow up. Edible Yields It is also worth noting that they are an edible plant in their own right. They not only produce edible seeds towards the end of the season – the petals are edible too. One thing to note, however, is that sunflowers are known to be allelopathic – in other words, they can suppress the growth of certain other plants when grown close by.3 You should avoid planting sunflowers too close to potatoes, for example. How To Grow Sunflowers As mentioned above, sunflowers could be grown in an ornamental bed or border, or in a vegetable garden. They will do best, as their name suggests, in an area that receives full sun. Though they can also potentially cope with partial shade, they do best where they receive at least 6-8 hours of direct sunlight per day. When choosing a location for growing sunflowers, it is important to understand that they have long tap roots (to anchor them well as they grow so tall). Soil Requirements They need to be planted in an area where the soil is deep enough to accommodate the root system – and they will do best where that soil is loose, moist and well-draining. Avoid areas with compacted soil, and areas with soils that are outside of the 6.0-7.5 pH range. The soil should be fertile and nutrient-rich, and it is a good idea to top-dress the area with plenty of organic matter before planting. Sowing In order to avoid pest issues, it is generally best to sow seeds indoors before transplanting seedlings later to their final growing positions. Seeds should be sown in small pots, modules or soil blocks indoors before the last frost, or, if you do prefer to sow directly, this should be done after you are certain that the last frost of the winter has passed. Ideally, you should wait until the soil has warmed to between 13-16°C. Choose a fertile and balanced, moist yet free-draining growing medium for sowing your seeds. Sow each seed by making a hole in the growing medium and placing a seed in each one, at a depth of around 2cm. Gently firm the soil back over the seed and water it in. Then leave it in a sunny spot for germination to take place. If you wish, you can improve your chances of success by sowing 2-3 seeds in each pot, and then removing the weaker seedlings once they emerge to leave one seedling per pot. One fun (and educational) game for kids is to have each child plant a sunflower, then have a ‘race’ to see whose grows the tallest the fastest. Each child should take care of their own seedling, watering it as required and trying different methods to affect their growth. Sunflower Plant Care Sunflowers do not require much care. They do not need much fertiliser and, in fact, will not thrive if you fertilise them too much. Coddled plants will tend to have weaker stems, that can break towards the end of the summer or in autumn. “The biggest problem with growing sunflowers that I come across is weak, elongated stems that snap when they are planted out,” shares Horticulturist and Consultant Colin Skelly. “Once the seedlings have true leaves, put them out into a cold frame or place them outside for a time during the day. This will allow the seedlings to grow ‘hard’ and produce stouter, stronger stems for planting out.” Watering When the seedlings are still small, especially if they are growing in a heated indoor space, you will have to regularly water to make sure that the growing medium around the root zone of your plants does not dry out. However, once the plants are more established, and certainly after you have hardened them off and transplanted them to their final growing positions, you should water far less frequently. Watering well on a less frequent basis rather than watering little and often is the best policy. It will encourage the plants to root deeply, which will make them stronger as the season progresses. Common Problems Slugs & Snails The biggest problems for sunflowers are often slugs and snails – they love sunflowers and can quickly destroy a young plant. Try to take natural measures to reduce slug and snail populations in your garden – such as attracting plenty of birds, amphibians and mammals that eat them. Choosing the right plants and creating different habitats (garden ponds and wild native hedgerows for example) should help. You can also place collars or barriers of material around young sunflower plants, and/or place slug traps nearby. Aphids Another thing you might notice about sunflowers is that ants may herd aphids onto them. One of the strange phenomena that occur in a garden is ants ‘farming’ aphids. But if ants herd aphids onto sunflowers, it is worthwhile remembering that this means they are keeping them away from your fruits and vegetables. This means sunflowers could also serve as useful companion plants in a kitchen garden because they can serve as a trap crop. References 1. Briggs, W. (2016, August). How do sunflowers follow the Sun – And to what end? Research Gate. Retrieved March 24, 2023, from https://www.researchgate.net/publication/305890471_How_do_sunflowers_follow_the_Sun_-_And_to_what_end 2. Sunflowers move from east to west, and back, by the clock. (n.d.). National Science Foundation. Retrieved March 24, 2023, from https://www.nsf.gov/news/news_summ.jsp?cntn_id=139271 3. Leather, G. R. (1983). Sunflowers (Helianthus annuus) are Allelopathic to Weeds. Weed Science, 31(1), 37–42. https://doi.org/10.1017/s004317450006851x
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Struggling With Potato Blight? Reduce The Chances Of It Taking Hold With These Steps
IN THIS GUIDE What Is Potato Blight? What Causes It? Identifying Potato Blight Reducing Blight Taking Hold Treating Potato Blight Cutting Your Losses References Potato blight is an annoying problem and one that many UK gardeners will experience at one time or another. Unfortunately, potato blight is a serious issue. It can cause significant reductions in yields and may, in extreme cases, mean that you lose your potato crop altogether. That said, it is important to recognise that, while it is nigh on impossible to get rid of, it is possible to identify and deal with it quickly, and to take steps to reduce the chances of potato blight taking hold. What Is Potato Blight? Potato blight is a fungal infection that can attack potato plants and other members of the same plant family, such as tomatoes.1 It is also referred to as ‘late blight’ to distinguish it from ‘early blight’ which is common in the US and elsewhere, but uncommon in the UK.2 If symptoms resembling those of blight occur earlier in the year in the UK, it is usually a case of magnesium deficiency instead.3 Throughout history, late blight has been responsible for a number of catastrophic crop losses. It was implicated in the famines in Europe in the 1840s, in 1845 in Ireland, and the following year in the Highlands of Scotland.4 An over-reliance on the potato crop meant that populations were left vulnerable, and many died when late blight destroyed the majority of the harvest. Fortunately, most gardeners and growers today don’t have all their eggs in one basket. Though blight is a common problem, it rarely destroys whole harvests. And even when the potato harvest does suffer, home growers usually have a range of other crops that may well have fared better in a bad year for potatoes. What Causes It? Potato blight is caused by a microorganism – a fungus called Phytophthora infestans.5 The spores can linger for years in the soil, and since they thrive in damp and soggy conditions, they will tend to be more prevalent when there has been a wet summer.6 When the fungus reaches the plants, it will infect them and spread – often very quickly – through the plant tissue. Identifying Potato Blight Tubers affected with late blight. Potato blight is usually first noticed as brown areas that appear on the foliage of potato (or tomato) plants. These brown areas will speedily spread into a wet rot that kills the leaves, spreading to the stems and turning them brown too. If nothing is done, the infection can spread from the leaves and stems to the potato tubers. If they become affected, potato tubers will have a reddish-brown discolouration below the skin and will become rotten and soft. Tuber blight may not be immediately obvious when the crop is harvested, but the tubers that have been affected will rot quite quickly in storage. Reducing Blight Taking Hold If blight is present in your area, then unfortunately there is not much you can do to entirely eliminate the risk that it will take hold in your potato crop. However, there are certain things that you can do to reduce the risk that it will become a major problem: 1) Grow Early Harvest Potatoes Firstly, you can consider growing only potatoes that will be harvested before it is likely that blight will become a problem. First early potatoes are harvested around July, and so will be out of the ground before the blight arrives in late summer. “My approach to avoiding potato blight is to grow first earlies, harvesting from late June to mid-July,” shares Colin Skelly, a Master Horticulturist. “Living in a mild, moist part of the UK, blight is unavoidable and resistant varieties only after a slight delay on the inevitable. First earlies are still wort growing and offer a great range of tasty and productive cultivars.” 2) Consider Blight Resistant Varieties ‘King Edwards’ It is worthwhile noting that even ‘blight resistant’ varieties of potatoes are not invincible. But you can significantly reduce the chances of severe infection if you choose those with the highest blight resistance levels. In the UK, some options are: ‘Athlete’ ‘Cara’ ‘Carolus’ ‘Orla’ ‘Sarpo Mira’ ‘Valor’ Some common and favourite varieties are particularly susceptible, and so it may be best to avoid these in areas where blight is a particularly pressing problem. These include: ‘Arran Pilot’ ‘King Edwards’ ‘Majestic’ ‘Sharpe’s Express’ 3) Take Care When Watering Water early in the morning if possible, so leaves have a chance to dry out before nightfall. And try to make sure you water plants at the base – delivering water to the roots where it is needed and avoiding getting the foliage wet. Wet leaves will make it more likely for blight to appear. 4) Ensure Good Ventilation Make sure you do not place your potato plants too close together and are not overcrowded. Good ventilation can help to reduce the incidence of fungal disease and keep plants as healthy and resilient as possible. 5) Earthing Up & Mulching Earthing up or mulching around your potato plants won’t keep blight away. But it might offer some level of protection to the edible underground portions of the plant, and ensure that even when the plants above the soil are affected, you still get an edible yield. 6) Implement Crop Rotation Finally, you can reduce the chances of a serious blight problem by making sure that you don’t grow potatoes (or other members of the same plant family) in the same location year after year. Ideally, you should have a four-year crop rotation plan in place for your annual growing areas. Treating Potato Blight It is important to check growing and stored potatoes regularly for signs that blight has taken hold. The quicker you can catch the problem, the less likely it is to spread widely to affect other plants, and the less likely it is that the blight will spread to affect the tubers as well as the above-ground portion of the potato plants. Early signs of blight To be forewarned about blight in your area, you can register for Blightwatch in the UK, which sends out alerts at postcode level.7 If you see signs of blight, quickly remove the affected plant material and burn it, or dispose of it well away from your garden and composting areas. Reducing The Spread Make sure you practice good hygiene – wash your hands and any tools, avoid touching other plants and spreading the disease. To reduce the chances of infection of plants currently unaffected, you can consider using anti-fungal organic treatments on the foliage of your plants. For example, you can spray 10g of bicarbonate of soda in 1 litre of water onto the tops and undersides of all the leaves. Do so early in the morning to avoid leaf scald. However, this and other anti-fungal treatments are only ever partially effective. You can also reduce the chances of late blight from setting in by using an activated hydrogen peroxide fungicide or a fungicide containing Streptomyces lydicus – a beneficial bacteria. However, if a bad fungal infection has already set in, then it may well be too late to do much. These solutions generally just help to avoid a problem from spreading further. Be sure to only ever spray an organic fungicide, and only ever as a last resort. Cutting Your Losses Depending on when exactly blight takes hold in your potato crop, it can be a good idea to cut your losses and remove all above-ground portions of your plants. Of course, this means that the tubers will not grow anymore, but it should mean that you are able to harvest the tubers. If 25% of the leaves on potato plants are affected, you should certainly cut off all the stalks near ground level. Be sure to rake up and carefully remove all the debris from the area. After around two weeks, the skins on the tubers will be hard and you can dig them up and eat them or store them for later. References 1. Schumann, G., & D’Arcy, C. (2000). Late blight of potato and tomato. APS. Retrieved March 23, 2023, from https://www.apsnet.org/edcenter/disandpath/oomycete/pdlessons/Pages/LateBlight.aspx 2. Early Blight. (n.d.). Bayer Crop Science UK. Retrieved March 23, 2023, from https://cropscience.bayer.co.uk/threats/diseases/potato-diseases/early-blight-potatoes/ 3. Potato – Magnesium deficiency. (2018). Ephytia. Retrieved March 23, 2023, from https://ephytia.inra.fr/en/C/21161/Potato-Magnesium-deficiency 4. The Irish Famine: Potato Blight. (n.d.). Ireland Story. Retrieved March 23, 2023, from https://www.wesleyjohnston.com/users/ireland/past/famine/blight.html 5. Potato Late Blight. (2019, July 22). CropWatch. Retrieved March 23, 2023, from https://cropwatch.unl.edu/potato/late_blights_description 6. Farm Advisory Scotland, & Burnett, F. (2017, December 22). Wet summer raises risk of potato storage rots. Farm Advisory Service. Retrieved March 23, 2023, from https://www.fas.scot/news/wet-summer-raises-risk-potato-storage-rots/ 7. Home. (n.d.). Blightwatch. Retrieved March 23, 2023, from https://blightwatch.co.uk/
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How To Grow Ginger Under Cover In A Greenhouse, Polytunnel, Or Inside Your Home
IN THIS GUIDE Overview Why Grow Ginger? How To Grow Ginger Habitat & Growing Conditions Ginger Plant Care Even in the temperate UK climate, you can grow tropical plants like ginger at home. However, it is important to understand that ginger is not a plant that you can just pop in your outdoor garden. This is something you will have to grow under cover in a greenhouse or polytunnel, or inside your home. If you plan and prepare correctly, and take care of your plants with their needs in mind, you can succeed in growing ginger in the UK. “It can be great fun growing tropical crops in the UK, even if the harvest might dubiously justify the effort,” says Master Horticulturist Colin Skelly. “There are ornamental gingers but growing from a supermarket stem sounds like a great project to get children engaged with where their food comes from!” Overview Botanical Name Zingiber officinale Common Name(s) Ginger Plant Type Perennial / Houseplant Native Area Island South-East Asia Hardiness Rating H1A Foliage Slender pseudo-stems Flowers Purple flowers; uncommon to see these in UK cultivation When To Sow February, March Flowering Months October, November Ginger is a perennial herbaceous plant – Zingiber officinale. It is generally grown for its underground stems, or rhizome, which are used fresh, or ground to make a common dried spice. Interestingly, this is not a plant that is found in the wild – it is only found in cultivation. The plant grows to an eventual height of between 30-100cm. It forms slender pseudo-stems that are sometimes harvested for an additional yield known as stem ginger. Inflorescences of yellow and purple flowers form on shoots that rise separately from the rhizome, though these are rarely seen when the plants are grown in temperate climates. Why Grow Ginger? Ginger is a very useful cooking ingredient and spice that can be very useful in a wide range of different recipes. It is a food-producing plant that can be grown at home even by those without a garden. You can grow it in a container even in the smallest of spaces. How To Grow Ginger The end of winter is a good time to plant ginger in temperate climates like ours here in the UK, but you can give this a try at any time of year when you are growing ginger inside. Choosing Rhizomes Ginger is grown from rhizomes (commonly referred to as root sections). These can be bought online or sometimes from local plant nurseries. You may also be able to root fresh ginger that you have bought from the shops. It is worth noting that ginger for sale in supermarkets may have been treated to prevent shoots from forming. If this is the case, soaking the root in water for 24 hours prior to planting may help (by washing away treatments used to slow growth). When choosing a rhizome, note that the larger it is, the more quickly the ginger will be produced. You are looking for a rhizome with small nodules similar to the chits that appear on potatoes. New growth will form from these small growth buds. Container Growing Choose a rich and fertile, moist but free-draining growing medium and a container that will allow that growing medium to dry out well between waterings while still retaining some moisture for your plant. Remember, when choosing a suitable container, that you are growing ginger mostly for what lies beneath the surface. So a tall, narrow pot that allows roots to delve deeper as the above-ground plants grow is the best option. Place your ginger rhizome into a pot or container with the green growth buds popping out just above the surface of the growing medium. Habitat & Growing Conditions It is important to remember, when choosing where to place your ginger plants in containers, how and where ginger grows in a more natural environment. Ginger thrives in moist to wet tropic environments. It grows best where daytime temperatures of between 18-28°C are maintained – though it can also cope in temperatures as low as 12-13°C and as high as 35°C. It will tend to go dormant at temperatures lower than those of the optimal range. Though ginger may prefer a partially shaded spot in hotter climates, when grown in the UK it will do best when given as much sun as possible. In order to encourage ginger grown indoors in our climate to root successfully, it can be helpful to provide gentle bottom heat (from a heated propagator, or heat mat, for example). However, ginger will often root and shoot successfully when simply placed in a warm position on a sunny windowsill. Ginger plants require relatively high humidity – and this can be one of the biggest challenges when growing ginger indoors in a temperate climate. Since central heating can really dry out the air, it can be beneficial to place ginger in a location where the humidity remains somewhat higher, such as on a kitchen windowsill close to the kitchen sink, or in a light, bright bathroom. Ginger Plant Care It is important to make sure that the growing medium around your ginger stays moist, but does not become waterlogged. You should water well but ensure that the medium and container are free-draining. When growing indoors, it may also be necessary to mist your plants to increase humidity levels. As your ginger plant shoots and begins to grow, it will be important to pot it up regularly. If it is doing well, by midsummer (having been planted in late winter) it should be in a rather large container (such as a 20-litre pot or grow bag, for example).
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Look Out For These Weeds! Gardeners Share 30 Common Types You'll Probably Recognise
IN THIS GUIDE What Are Weeds? Categories Of Weeds Annual Weeds Biennial Weeds Perennial Weeds Ephemeral Weeds Types Of Common Weeds 1) Nettles 2) Docks 3) Creeping Thistle 4) Creeping Buttercup 5) Japanese Knotweed 6) Couch Grass 7) Cleavers AKA ‘Sticky Willies’ 8) Common Mouse-Ear 9) Green Alkanet 10) Wood Avens 11) Common Ragwort 12) Bindweed 13) Ground Elder 14) Alleluia 15) Celandine 16) Enchanter’s Nightshade 17) Storksbill 18) Yarrow 19) Cuckoo Flower 20) Rosebay Willowherb 21) Common Chickweed 22) Horsetail 23) Daisy 24) White Clover 25) Common Dandelion 26) Bird’s Foot Trefoil 27) Scarlet Pimpernel 28) Groundsel 29) Slender Speedwell 30) Red Clover Are Weeds Bad? Know Your Enemy References No matter how the size or style of your garden, or whether you are a novice or seasoned gardener, there is one thing that unites us all: the battle against weeds. While some weeds can be aesthetically pleasing to the eye, for the most part, they are a nuisance and seem hell-bent on choking out and destroying our prized and precious plants. While there are some preventative measures you can take, as a gardener, it is wise to accept that weeds are an unavoidable part of gardening. Dealing with weeds can be a frustrating, laborious and often daunting task and trying to tackle them can feel overwhelming, to say the least. However, there are a number of things you can do to make this undesirable job more manageable, and the most important one is identification. Successfully identifying weeds can help you understand exactly what you need to do to get rid of them. In this article, we will introduce you to the most common weeds found in gardens in the UK because, in the world of weeds, knowledge is power. What Are Weeds? Simply put, a weed is a plant in an undesirable location. The Oxford Dictionary defines it as “a wild plant growing where it is not wanted, especially among crops or garden plants”.1 Interestingly, the term “weed” has no botanical significance. Wild plants growing where they are wanted would not be defined as weeds. On the other hand, wild plants growing in your garden where they are not wanted would be considered weeds. Essentially a weed is determined by the context in which it is growing. Categories Of Weeds There are three main categories of weeds in regards to the characteristics in which they grow, and these are as follows: Annual Weeds Annual weeds have an average life span of one year and germinate and spread by seed. There are both winter and summer types of annual weeds. Winter annual weeds tend to germinate in late summer or early autumn, lie dormant in winter and grow actively in spring. Summer annual weeds germinate in spring, grow through summer and die out in the winter months. Biennial Weeds Biennial weeds have an average life span of two years; they germinate and form rosettes in their first year and produce flowers, fruits and seeds in their second year before dying out. Perennial Weeds Perennial weeds are the beasts that return year after year. They usually produce long taproots, as well as seeds, and are generally the hardest weeds to control. Ephemeral Weeds “There is one more category that sits between annual and perennial weeds – ephemeral,” shares Dan Ori, a Horticultural Instructor and Consultant. “Ephemeral weed seeds lie dormant in the winter, through the year these weeds will normally spread through a rapid cycle of germinating, growing, flowering, setting seed and dying. “The rapid nature of their development makes regular weeding essential for their control. “A few common names of ephemeral weeds you may have heard of are Groundsel, Chickweed, Shepherd’s purse and Wavy bittercress.” Types Of Common Weeds Now that you have a nice clear understanding of what weeds are and what they are capable of, the next step is to learn how to identify them. We have put together a comprehensive list of all the weeds you are most likely to encounter in your garden as well as some tips and tricks on how to expel them. So let’s get started! 1) Nettles BOTANICAL NAME: Urtica dioica PLANT TYPE: PERENNIAL / ANNUAL UK NATIVE: YES Topping our list of weeds are nasty nettles. There are both perennial and annual types of nettles which both grow in clumps, reaching up to 1.2m in height. Perhaps one of the most easily recognisable weeds, they can quickly engulf borders and can also give unprotected skin a jolly nasty sting. Perennial nettles have creeping roots and are particularly troublesome in loose, newly cultivated soil, where they can quickly steal much-needed water and nutrients from other plants. The annual types of nettles do not have long-lasting roots; however, they do produce a prolific amount of seeds from a young age and can wreak absolute havoc in vegetable gardens. The good news is that nettles can be controlled by weedkillers which should be applied when the plant is in vigorous growth. You can also dig the entire plant out of the ground – be sure to wear gloves – and young seedlings can be removed by hoeing. It is worth mentioning, however, that nettles are a vital food source for British butterflies, so if you have a patch of them that isn’t interfering with your garden, you may wish to leave them be. 2) Docks BOTANICAL NAME: Rumex crispus PLANT TYPE: PERENNIAL UK NATIVE: YES Before we go into the reasons why docks are such an annoyance for gardeners, we should first point out that, if you have been stung by our previous weed, it’s claimed that dock leaves neutralise the effects – so credit where credit’s due, they aren’t all bad.2 That said, once established, they are more of a pain than a stinging nettle sting! Easily identified by their broad leaves and distinctive seedheads, docks are one of the most common weeds found in the UK and are bloomin’ hard to eradicate. Docks have a thick, branched taproot which can grow up to 90cm in length and can regrow if damaged. They also produce seeds in abundance which germinate easily and can also remain and survive in the soil for 50 years.3 The trick with docks is to try digging isolated specimens out. Only the first 12-15cm of rootstock has the power to regenerate so if you remove that successfully there should be no regrowth. Docks are most vulnerable in spring, so that’s the time to tackle them. Dock seedlings should be sprayed with weedkiller, killing them off before they have a chance to establish themselves. 3) Creeping Thistle BOTANICAL NAME: Cirsium arvense PLANT TYPE: PERENNIAL UK NATIVE: YES When it comes to creeping thistle, you are going to want to get on top of the problem fast as, once established, this plant can be extremely difficult to eradicate completely. Creeping thistle spreads using lateral roots; these roots are brittle and easily reshoot when broken, making this plant a really tricky customer. Uncontrolled thistle will compete with your plants for light, water and nutrients. The spreading roots of creeping thistle mean that the plant grows in large clumps, producing spiny leaves and flowering stems which can grow up to 1m in height. The dark, purple flowers, typical of the thistle family, bloom from July to September. The best time to combat thistles with weedkiller is when they are growing vigorously but haven’t begun to flower. Digging up thistles can cause problems as they can easily regenerate when roots are broken. With a widespread, overgrown thistle problem, digging the plants out could take many seasons. You will need to weaken the plant by cutting the top growth over a number of years, which should be done before the flower heads show colour. 4) Creeping Buttercup BOTANICAL NAME: Ranunculus repens PLANT TYPE: PERENNIAL UK NATIVE: YES Whilst the creeping buttercup does produce rather charming, yellow flowers, beloved by children trying to discern who likes butter, the plant itself is a rather irritating issue for gardeners. This perennial weed is most commonly found in lawns and borders, or other areas with bare soil. And, where there is moisture, it will grow strong and set deep roots. Creeping buttercup uses deeply penetrating roots to spread – they branch out from every leaf node to form a surprisingly sturdy underground network. To combat creeping buttercups in lawns, you can use a rake in springtime to lift the roots, then use a lawnmower to cut them. Aerating your lawn in autumn will improve the drainage, and reduce creep. A good old-fashioned trowel will help you dig out fledgeling roots before they have a chance to take hold, too. 5) Japanese Knotweed BOTANICAL NAME: Fallopia japonica PLANT TYPE: PERENNIAL UK NATIVE: NO Few weeds strike as much terror in the hearts of gardeners than Japanese knotweed. This rapidly spreading plant dies back to ground level in winter but, by early summer, its bamboo-like stems shoot from the ground, reaching heights of up to 2 metres. Japanese knotweed can be identified by its reddish-purple, fleshy shoots and crimson-pink buds which produce white flowers in late summer and early autumn. This nasty weed can be devastating not only for your garden but also for the prospects of your house if you are hoping to sell it. While it is not illegal to have Japanese knotweed growing in your garden, you are required to control it.4 Controlling this weed is no walk in the park. Even if digging out this deeply penetrating plant is possible, it has to be disposed of as controlled waste at a licensed site.5 For this reason, if you are experiencing issues with this formidable weed, we highly recommend seeking a specialist to assist you in its removal and disposal. See our interactive map to discover where Japanese Knotweed has been recorded in your area. 6) Couch Grass BOTANICAL NAME: Elymus repens PLANT TYPE: GRASS UK NATIVE: NO Couch grass, or twitch grass, is a well-known enemy among gardeners. This trouble maker forms wiry, underground stems, with creeping shoots that pop out of the ground and take control of garden beds. This perennial weed is tricksy and looks like a normal tuft of grass, but underneath it will be forming dense networks of roots, spreading rapidly and choking the growth of nearby, wanted plants. For small, isolated infestations, hand weeding can go a long way for couch grass and is best done in the springtime, before it re-establishes itself around bulbs. Where lawns are concerned, unfortunately, there isn’t a weedkiller that will leave the lawn unharmed. If couch grass has invaded your lawns, you may be better off killing off both the weed and the lawn: dig over the soil and prepare the area for re-sowing or re-turfing. 7) Cleavers AKA ‘Sticky Willies’ BOTANICAL NAME: Galium aparine PLANT TYPE: ANNUAL UK NATIVE: YES Whilst there is much fun to be had with this weed, which you can stick to unsuspecting peoples’ clothing, cleavers are no fun for gardeners. Cleavers can be easily identified by their sprawling stems which can grow to a metre in length. Their leaves are slender, and the plant produces little green-white flowers in clusters from May to August which develop into green or purple fruits. The problem with this plant is the seeds which are produced in mass quantities of up to 400 per plant. The seeds are easily distributed and can also stay in the soil for up to six years. Whilst individual weeds are relatively easy to uproot and remove, if allowed to establish, this plant can be a persistent pest. This is a weed you want to hand pull out as soon as it rears its ugly head. You can also avoid introducing cleavers to your garden by giving your clothes, or your pet’s fur, a good brush down after walks. 8) Common Mouse-Ear BOTANICAL NAME: Cerastium alpinum PLANT TYPE: PERENNIAL UK NATIVE: NO 9) Green Alkanet BOTANICAL NAME: Pentaglottis sempervirens PLANT TYPE: PERENNIAL UK NATIVE: YES 10) Wood Avens BOTANICAL NAME: Geum urbanum PLANT TYPE: PERENNIAL UK NATIVE: YES 11) Common Ragwort BOTANICAL NAME: Senecio jacobaea PLANT TYPE: BIENNIAL / SHORT-LIVED PERENNIAL UK NATIVE: YES 12) Bindweed BOTANICAL NAME: Calystegia sepium PLANT TYPE: CLIMBER UK NATIVE: NO 13) Ground Elder BOTANICAL NAME: Aegopodium podagraria PLANT TYPE: PERENNIAL UK NATIVE: NO 14) Alleluia BOTANICAL NAME: Oxalis acetosella PLANT TYPE: PERENNIAL UK NATIVE: YES 15) Celandine BOTANICAL NAME: Ficaria verna PLANT TYPE: PERENNIAL UK NATIVE: NO 16) Enchanter’s Nightshade BOTANICAL NAME: Circaea lutetiana PLANT TYPE: PERENNIAL UK NATIVE: YES 17) Storksbill BOTANICAL NAME: Erodium cicutarium PLANT TYPE: ANNUAL UK NATIVE: NO 18) Yarrow BOTANICAL NAME: Achillea millefolium PLANT TYPE: PERENNIAL UK NATIVE: YES 19) Cuckoo Flower BOTANICAL NAME: Cardamine pratense PLANT TYPE: PERENNIAL UK NATIVE: YES 20) Rosebay Willowherb BOTANICAL NAME: Chamaenerion angustifolium PLANT TYPE: PERENNIAL UK NATIVE: YES 21) Common Chickweed BOTANICAL NAME: Stellaria media PLANT TYPE: ANNUAL (Ephemeral) UK NATIVE: YES 22) Horsetail BOTANICAL NAME: Equisetum arvense PLANT TYPE: PERENNIAL UK NATIVE: NO 23) Daisy BOTANICAL NAME: Bellis perennis PLANT TYPE: PERENNIAL UK NATIVE: YES 24) White Clover BOTANICAL NAME: Trifolium repens PLANT TYPE: PERENNIAL UK NATIVE: YES 25) Common Dandelion BOTANICAL NAME: Taraxacum officinale PLANT TYPE: PERENNIAL UK NATIVE: NO 26) Bird’s Foot Trefoil BOTANICAL NAME: Lotus corniculatus PLANT TYPE: PERENNIAL UK NATIVE: YES 27) Scarlet Pimpernel BOTANICAL NAME: Anagallis arvensis PLANT TYPE: ANNUAL UK NATIVE: YES 28) Groundsel BOTANICAL NAME: Senecio vulgaris PLANT TYPE: ANNUAL (Ephemeral) UK NATIVE: NO 29) Slender Speedwell BOTANICAL NAME: Veronica filiformis PLANT TYPE: PERENNIAL UK NATIVE: NO 30) Red Clover BOTANICAL NAME: Trifolium pratense PLANT TYPE: PERENNIAL UK NATIVE: YES Are Weeds Bad? It is also worth noting that not all weeds are “bad”, as Danny Clarke, reputable Garden Designer and TV Personality, shares: “I think we should learn to love our weeds a little bit more. “We should not be too tidy in our gardens and should instead allow the garden to do its own things to an extent. I believe in challenging what a beautiful garden is. “For me, it’s not about a lawn in the middle with narrow borders around the edge with all the shrubs and plants lined up like soldiers on duty. “I’m about bringing in as many plants into the space as possible and letting them do their own thing.” Many plants widely regarded as weeds are also grown intentionally because of the benefits they provide. Beneficial weeds are invasive, usually non-domesticated plants, that can provide protection or other benefits to plants, contribute to soil health or have ornamental value. “Leave patches of grass unmown and don’t pull up weeds too quickly, as most plants typecast as weeds are incredibly beneficial to wildlife and are actually beautiful flowering plants,” says Garden Writer Debi Holland. For the most part, however, weeds are an absolute pain in the backside for us gardeners and need to be controlled and/or completely eradicated from our gardens. Uncontrolled weeds can interfere with our gardens, and our lives, in a variety of ways including: Competing with wanted plants’ resources such as sunlight, nutrients in the soil, water and space for growth. Providing a host for plant pathogens, infecting and degrading the quality of our wanted plants. Providing food or shelter for pests such as seed-eating birds and fruit flies, which would otherwise struggle to survive seasonal changes. Damaging the integrity of buildings and garden structures. Know Your Enemy At the end of the day, there will always be weeds and they will always be a big part of gardening. Prevention is the best method but, more importantly, identifying the weed and understanding its growth habits are the best way to stop it in its tracks. We hope this article has given you the know-how to deal with some of the most common UK garden weeds. The best thing we can recommend when it comes to weeds is to do your research, put your back into and take your garden back! References 1. weed. (n.d.). Oxford Dictionaries. Retrieved March 14, 2023, from https://www.oxfordlearnersdictionaries.com/definition/american_english/weed_1 2. Cottam, L. (2019, May 15). Why do nettles sting? Do dock leaves help? Woodland Trust. Retrieved March 14, 2023, from https://www.woodlandtrust.org.uk/blog/2019/05/why-do-nettles-sting/ 3. Docks. (n.d.). Royal Horticultural Society. Retrieved March 14, 2023, from https://www.rhs.org.uk/weeds/docks 4. How to stop Japanese knotweed from spreading. (2023, February 17). GOV.UK. Retrieved March 14, 2023, from https://www.gov.uk/guidance/prevent-japanese-knotweed-from-spreading 5. Council, M. C. (n.d.). Japanese Knotweed. Manchester City Council. Retrieved March 14, 2023, from https://www.manchester.gov.uk/info/709/looking_after_parks_and_open_spaces/5753/weeds/2
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10 Incredible Acer Tree Types From The Chairman Of The Maple Society
IN THIS GUIDE Maple Society Favourites 1) A. campestre (Field Maple) 2) A. rubrum (Red Maple) 3) A. saccharum (Sugar Maple) 4) A. saccharinum (Silver Maple) 5) A. platanoides (Norway Maple) 6) A. pseudoplatanus (Sycamore) 7) A. griseum (Paperbark Maple) 8) A. palmatum 9) A. japonicum 10) A. davidii (Snake Bark Maple) References Acers are a genus of trees and shrubs commonly referred to as maples and a number of the 128 species within this group can be successfully grown in the UK.1 Many Acer species are popular as ornamental trees – prized in particular for their autumn colour. “Acers seem to be doing really well in the current climate, so I’d suggest growing one,” shares Climbing Arborist Cecily Witall. “Have a look at what is available to you and look at trees that come from areas that have cold winters but lots of heat in the summer. Look towards their natural habitats and use what you can.” They make popular specimen trees in many gardens, but the problem is, there are literally thousands of different cultivars to choose from. In this article, we explore some of the best options for UK gardeners to consider. Maples can be both trees and shrubs and can vary significantly in shape, size, colour, form and habits. Some are suitable for small gardens, and some are even suitable for growing in containers. Maple Society Favourites We asked Agustin Coello-Vera from The Maple Society to share some of his favourite Acer varieties. “This question is often asked by visitors to my forest garden and my answer is that it depends on the day,” he says. “Almost every maple shows wonderful colours, including red, orange, yellow, purple, black, or golden brown. Acer griseum “Not only are the leaves beautiful in the autumn, but many maples also present a good display of fruits in various colours. “Maples may have splendid bark, such as the snake bark maples or the paperbark maple, Acer griseum. “Many maples flower profusely in spring, such as the Norway maple, A. platanoides, which provides a wonderful display of clear yellow flowers.” If, like Agustin, you are struggling to choose a favourite, read on for more suggestions for you and your garden: 1) A. campestre (Field Maple) The UK’s only maple that is native to these shores, the field maple can be an excellent garden tree. It is commonly chosen as a garden tree or a tree for city parks because of its compact growth habit, its tolerance of atmospheric pollution and, of course, its stunning autumn foliage. One of the reasons why it is a good idea to consider a native maple is that as a native plant, it offers a lot more to native wildlife. The field maple is attractive to aphids, which means that it also benefits their predators such as ladybirds, hover-flies and birds. “One of my favourite plants is the field maple, as it is a real champion of a tree that can grow on chalky soil,” shares Gardener Kim Wilkie. Many species of moths also benefit from the tree, and feed on its leaves. The flowers provide nectar for pollinators such as bees, and birds and small mammals eat the fruits. The field maple can grow in most fertile but well-drained soil types, in full sun or partial shade. It can cope with a range of less-than-optimal conditions and may form as a shrub in chalky soils. As well as being a specimen tree, the field maple can also be coppiced, or used as a hedgerow plant. “One cultivar I have planted many of as street trees and in gardens of all sizes is Acer campestre ‘Queen Elizabeth’ also known as ‘Evelyn’,” says RHS qualified Horticulturist Dan Ori. “Its compact relatively columnar shape and its tolerance of drought and most soil types/pH make it a great pick.” 2) A. rubrum (Red Maple) The most abundant native tree in the northeastern United States, the red maple can also be grown in the UK.2 It is incredibly adaptable to soil type and conditions, and can cope well in full sun or partial shade. Of course, this is a stunning ornamental tree. As the name suggests, the leaves turn bright red in autumn – these autumnal displays will be most vivid when the red maples are planted in acidic soils. Acer rubrum can be good for city planting because they are fairly tolerant of air pollution. However, the trees have low, invasive root systems which can cause damage to paving etc. It is also important to note that this tree can restrict the growth of a number of other plants when they are grown close by. Since this is an Acer that grows into full-sized trees up to 30m in height, this is not necessarily the best choice for smaller or more restricted spaces. However, where the space is available, these can be truly stunning specimen trees. A number of cultivars make excellent bonsai, and can even be grown in containers. Some red maple cultivars to consider in the UK are: A. rubrum ‘October Glory’ Dependable autumn colour and vigorous growth. A. rubrum ‘Red Sunset’ Good drought/heat tolerance, upright, vigorous growth habit and orange-red autumn colour. A. rubrum ‘Northwood’ Open habit with branches 45-degree angle to the trunk forming an attractive oval crown. Its colour is not as intense as other cultivars. 3) A. saccharum (Sugar Maple) The sugar maple is another North American native Acer that can also be grown successfully in some southern parts of the UK. In addition to being known for its brightly coloured autumn foliage, the sugar maple is of course also known for being the primary source of maple syrup. Unfortunately, the seasons and climate conditions here in the UK mean that the potential for worthwhile sap production and harvesting is negligible – but that does not mean that you cannot still consider growing these attractive trees. These are large, deciduous trees that will grow up to 20m tall, with dense oval or rounded crowns, and five-lobed leaves that turn yellow, orange and reddish in the autumn. These trees can be grown as specimen trees in full sun or shade, in moist but well-drained soil. Though it can be a useful specimen tree in Cornwall and other warm and protected southern gardens, it should be noted that this too is a bad companion plant, and may inhibit the growth of a range of other plants grown close by. 4) A. saccharinum (Silver Maple) Another very vigorous deciduous tree, the silver maple should not be confused with the similarly named species above. It will grow to more than 12m in height and be wider than 8m once fully grown. It will not be the best choice for smaller gardens, as it has invasive roots that can do damage to pipes or structures. It can also have allelopathic (growth-slowing) effects on nearby plants. It is also worthwhile noting that this is a comparatively short-lived tree – it will typically live between 125 and 140 years. Like other maples mentioned above, however, this is another maple species that can provide amazing autumn colour in a large, sheltered garden. It can do well in many different soil types as long as the soil is moist but well-drained. The shallow root system can also be useful for use in erosion control in certain situations. 5) A. platanoides (Norway Maple) The Norway maple was introduced to the UK in the 17th Century.3 Though not a native plant, this is another tree that can be beneficial for wildlife in a UK garden. The leaves are eaten by a range of caterpillars and a number of birds and small mammals eat its seeds. This is a broadleaf tree that can grow to an eventual height of around 25m. Leaves will fade to yellow and occasionally to ruddy brownish red before they fall in the autumn. In spring, conspicuous clusters of yellow flowers form on the bare branches. This plant will grow in Britain in all but the very poorest of soils, so it can be an interesting specimen tree to consider for many gardens. However, it is worth noting that like many maples, this tree can also have a detrimental effect on certain other plants grown close by. 6) A. pseudoplatanus (Sycamore) Not to be confused with the similar species above, the sycamore maple, commonly called simply ‘sycamore’ in the British isles is another option to consider. It is believed that the sycamore may have been originally introduced to our shores by the Romans, or in the 1500s.4 It is believed to have naturalised from around the mid-1800s. This broadleaf tree can grow up to 35m high, and live for 400 years or so – meaning it is important to be careful where it is planted. The ‘helicopter’ seeds spread this tree quickly and it has colonised native woodlands to the detriment of native species. However, it can be an option to consider in larger gardens, where, like other native and naturalised maples, it has benefits for a wide range of garden wildlife. It may be particularly beneficial as part of a wild break or shelterbelt. 7) A. griseum (Paperbark Maple) Another tree to consider for certain UK gardens is the paperbark maple. It is a small, spreading tree which is deciduous, with leaves that turn a brilliant orange and red in autumn. The tree is also known for its attractive peeling and paper-like bark, which has a lovely rich chestnut-brown colour. The tree can reach an eventual height of 8-12m and can be a good choice for a small specimen tree in many gardens. It can grow successfully in a range of soil types and in full sun or partial shade, so it is common to find it in borders, or front gardens. 8) A. palmatum If you are looking for a smaller tree or shrub, then Acer palmatum (a type of Japanese maple) is a species that provides a huge array of cultivar options. These Asian maples are all extremely popular for their astounding colours and attractive, compact forms. There are cultivars that have a huge range of different colours in their foliage, and there is also variety in leaf form and growth habit. “Generally speaking, Japanese maples do not do well in alkaline soil,” says Dan Ori. “In layman’s terms, it is like putting them on a diet where they can’t access nutrients as they need to; they can survive and even have a long life in high pH but they do not thrive and will present establishment and health problems for the gardener to mitigate.”5 Waterlogging and compacted soil are ‘no-nos’ for these plants, but other than that they are surprisingly un-fussy. In terms of sun, they can thrive in full sun or dappled or partial shade. They will do best in more sheltered sites but can also cope with some wind exposure. Some A. palmatum cultivars to consider are: A. palmatum ‘Bloodgood’ A. palmatum ‘Lace Lady’ A. palmatum ‘Dissectum Viridis’ A. palmatum var. dissectum ‘Seiryu’ A. palmatum ‘Beni-Maiko’ A. palmatum ‘Little Princess’ A. palmatum ‘Kagiri-nishiki’ A. palmatum ‘Katsura’ A. palmatum ‘Osakazuki’ A. palmatum ‘Shin-deshojo’ Though there are plenty of other beautiful options within this type of maple to consider. 9) A. japonicum Other Japanese maples not in the group mentioned above include those in the Acer japonicum species. These Acers are also known as Amur maples or fullmoon maples. These are small, deciduous trees which very rarely grow above around 10m tall, and are often much smaller. Though less commonly cultivated as ornamental plants than Acer palmatum, these can also make interesting additions to a UK garden. Two cultivars of A. japonicum that have received the Horticultural Society’s Award of Garden Merit are: A. japonicum ‘Vitifolium’ A. japonicum ‘Aconitifolium’ So one of these could also be worthwhile considering. 10) A. davidii (Snake Bark Maple) Finally, one other more unusual maple to consider for your garden is the snake bark maple. This is a small, spreading tree that can grow up to around 10m in height. It has triangular, mid-green leaves that turn yellow or orange in the autumn. As the name suggests, these Acers are also characterised by their bark, which does have winding patterns on it that look a little like snakes. So, which maples will be right for your garden? The above should have given you a great place to start when making the right choices for your space. References 1. Maples (Genus Acer). (n.d.). iNaturalist UK. Retrieved March 9, 2023, from https://uk.inaturalist.org/taxa/47727-Acer 2. Red Maple. (n.d.). National Wildlife Federation. Retrieved March 9, 2023, from https://www.nwf.org/Educational-Resources/Wildlife-Guide/Plants-and-Fungi/Red-Maple 3. Trust, W. (n.d.). Norway Maple (Acer platanoides). Woodland Trust. Retrieved March 9, 2023, from https://www.woodlandtrust.org.uk/trees-woods-and-wildlife/british-trees/a-z-of-british-trees/norway-maple/ 4. Trust, W. (n.d.-b). Sycamore (Acer pseudoplatanus). Woodland Trust. Retrieved March 9, 2023, from https://www.woodlandtrust.org.uk/trees-woods-and-wildlife/british-trees/a-z-of-british-trees/sycamore/ 5. Cregg, B. (2014, November). Right Tree: Right Place – Alkaline Soils. Michigan State University. Retrieved April 3, 2023, from https://www.canr.msu.edu/hrt/uploads/535/78626/RightTreeAlkalineSoilred.pdf
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How To Grow Sempervivum ‘Houseleeks’ With Tips From Nursery Grower Becky Scott
IN THIS GUIDE Overview Common Varieties How To Grow Sempervivum Ongoing Sempervivum Care Common Problems References As you might imagine, Sempervivum ‘Houseleek’ has nothing to do with leeks, the vegetables you sometimes use for cooking. That leek, scientific name Allium porrum, is from the genus of flowering plants that includes shallots, chives, leeks, garlic, onion, and all the other delicious aromatics that are familiar dinner ingredients. This ‘leek’ on the other hand, is a succulent – one of the colourful, trendy, and easy-to-care-for plants that you see in beautiful little displays like the one below. In this guide, we’ve worked with Becky Scott, Co-Owner of the plant nursery Sempervivums By Post. “Sempervivums are great outdoor plants and easy to look after,” says Becky. “You can grow them in pots, containers, or in the ground in a rockery. The choice of different colours and forms is tremendous.” If you’re looking for succulents to grow in your home, Sempervivum should be your first port of call. These stylish and undemanding plants bring flair to even the most mundane living spaces. You may also see this plant referred to as ‘Hens and Chickens’. “I love sempervivums and mainly use them as houseplants, but I do put them outside during the summer and they enjoy it,” says Tamsin Westhorpe, a professional Gardener. “They are great value plants and can be kept in tiny pots.” Overview Botanical Name Sempervivum Common Name(s) Houseleek, Hens and Chickens Plant Type Succulent Native Area Europe, North Africa, Middle East Hardiness Rating Mostly H5 – H7 Foliage Evergreen, fleshy leaved rosettes Flowers Some pink or pale yellow flowers When To Sow March, April, May Flowering Months July, August These plants are evergreen succulents whose name hints at their perennial nature – ‘Sempervivum’ means ‘always alive’ in Latin.1 Its interesting visual characteristics are immediately inviting, and whether you decide to grow Sempervivum outdoors or in a container, you’re guaranteed a good show. Common Varieties There are a number of naturally-occurring species and thousands of garden varieties in this family, covering a full rainbow of colour. There’s no space to introduce all the varieties here, so we’ve chosen a handful that have received the RHS’s Award of Garden Merit.2 S. guillaumes This variety of Sempervivum is a perfect demonstration of the striking form and colour palette you can expect from the plant. Although colours may vary, they’ll almost always be as vibrant and engaging as the Guillaumes. The plant is, by nature, mat-forming – that means it spreads out along the ground in dense mats, propagating through ‘offsets’ – nearly-grown plant babies that erupt into growth when they touch ground. Each spiky cluster is called a ‘rosette’, and the thick, sometimes waxy leaves hold the plant’s water supply; Guillaumes’ rosettes grow about 2cm in diameter. Like all Sempervivum, Guillaumes are naturally hardy thanks to their rugged North African, Middle Eastern, and Balkan heritage. S. tectorum The common houseleek, as this variety is known, has tons of nicknames including ‘Homewort’, ‘Imbroge’, ‘Poor Jan’s Leaf’, ‘Welcome-Home-Husband-However-Drunk-You-Be’ and more. None of the names give much of a clue about the plant, though. And none describe its green fading gracefully into deep red, or the attractive clusters of lightly-spiked leaves – nor the complex colour palette that the plant provides year-round. This is a great little Sempervivum that will make a great impression on any gardener. It’s just as unfussy as other varieties, but grows slightly larger in size – up to about 10cm. S. arachnoideum The boffins amongst you may recognise the ‘arachno’ in this variety’s name as being indicative of spiders. Don’t worry, though: It’s not named for a tendency to attract these eight-legged critters into your house. Rather, this houseleek variety is named after its striking cobwebbish aesthetic. The stringy white hairs at the tip of each head form a web around the spiky leaves, making an unusual and eye-catching visual contribution to any plant container. Individual rosettes grow to about 3cm across, and like all Sempervivums, this variety is mat-forming. Expect to see dashes of red year-round, and a bit of pink. How To Grow Sempervivum This variety of plant likes full sun, and well-drained soil. It’s relatively easy to care for in the UK because of its origins in demanding environments. With Sempervivum, the one thing you want to look out for is overly wet winters. “If you don’t provide sempervivums with a mix of soil and grit, to provide good drainage, the roots can rot in the winter wet,” explains Becky. S. charadzeae Although this plant can handle a lot, it’ll need a hand being sheltered from the icy blasts we’re prone to get later in the year. You can either cover the plant or bring it inside for a winter container holiday. Growing From Seed You can grow Sempervivum from seed. To do so, plant them in pots at least 5cm in diameter, push the seed gently below the surface, then leave them to germinate somewhere well-lit and at least 21°C for up to 5 weeks. If all goes well, you’ll see some germination. In this case, just leave the plant to grow for a while, then move onto the next section. If all doesn’t go well, which sadly is more likely with Sempervivum from seed, whack the pots in the fridge for a couple of weeks, then take them out and put them back in the well-lit warm spot – hopefully this time around you’ll see germination. Due to how fiddly and unpredictable this process can be, a lot of people prefer to grow Sempervivum from offsets. This is essentially cloning the parent plant, and is a much more reliable way to grow houseleek. “Our advice is don’t grow sempervivums from seed,” says Becky. “Named varieties are much, much better. They’ve been professionally selected from huge batches of plants grown from seed, usually with specifically chosen parents to give the best chance possible of producing something different.” “If you’re lucky, one in a thousand plants you grow from seed might be good enough – with the rest below standard.” Planting Sempervivum This plant likes a well-drained soil, as we’ve said. Sandy or loamy is best. “We suggest a mix of John Innes and horticultural grit,” recommends Becky. It’s not a fussy plant, and will grow well in solitary pots, shared containers, flowerbeds, and even gravelly rock gardens. “It’s best to grow sempervivums on their own. Select the types you like the look of and mix them up. “Don’t plant them with other outdoor succulents, such as sedums, because the latter will spread too fast and take over.” Planting Sempervivums is as simple as filling a container with the right type of soil, placing the plant in the soil, then ensuring the roots are covered. “Sempervivums spread by offsets, but once a rosette flowers, it will die, which can leave gaps in the planting,” shares Master Horticulturist Colin Skelly. “Just replant some of the offsets to fill the gaps left.” You’ll want to compact the earth as well to give the plant a secure footing. Ongoing Sempervivum Care Light Let there be light! Sempervivums love the sunlight, and will do better the more they’re exposed to it. If you’re planting Sempervivums in your garden, give them pride of place in the brightest spot. They’ll catch the eye of any visitors, and lend a tremendous visual element to your garden’s aesthetic. Watering This plant doesn’t typically need much water. For the most part, occasional rain should cover your Sempervivum watering needs, but if you’re going through a drought, a light sprinkle every once in a while won’t go amiss. Check the soil moisture with your finger before watering – a good couple of inches of soil should be mostly dry before you need to add more water. Common Problems There are a few pests that enjoy dining out on Sempervivum. Sempervivum Leaf Miner This hoverfly larva literally mines the leaves of a Sempervivum plant, to get at the good stuff inside. You’ll see limp, discoloured leaves, and if you examine more closely, you’ll find small maggots. To control leaf miner larvae, just pick off and dispose of them when you find them. Slugs & Snails Sadly your Sempervivum will find no reprieve from these common garden pests. Slugs and snails will treat themselves to a little nibble here and a little nibble there, eventually causing massive damage if left unchecked. To control against slugs and snails, you can make a border of sharded glass, use poisons, or simply remove them manually. References 1. Sempervivum definition and meaning | Collins English Dictionary. (2023). In Collins Dictionaries. Retrieved March 23, 2023, from https://www.collinsdictionary.com/dictionary/english/sempervivum 2. Ornamental AGM Plants. (2021b, July). Royal Horticultural Society. Retrieved March 23, 2023, from https://www.rhs.org.uk/plants/pdfs/agm-lists/agm-ornamentals.pdf
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Growing Laurus Nobilis ‘Bay Tree': A Popular Ornamental For Year-Round Interest
IN THIS GUIDE Overview Why Grow Bay? Bay Tree Varieties How To Grow A Bay Tree Bay Tree Plant Care Harvesting Bay Leaves References The bay tree, or Laurus nobilis, is an elegant evergreen shrub grown for its deliciously aromatic leaves that can be used as a seasoning in cooking. Although bay trees can grow as high as 7.5m or more, they are often pruned or kept in containers or pots to limit their height and spread. Bay trees are slow-growing and have become a popular ornamental tree, often used for formal displays Their gorgeously dark green foliage can be easily pruned, clipped and trained into neat topiary shapes. Being evergreen, bay trees provide year-round interest, texture and structure to the garden. They also produce small, star-shaped, yellow-green flowers which bloom in spring which develop into dark purple berries in autumn. Overview Botanical Name Laurus nobilis Common Name(s) Bay Tree Plant Type Tree Native Area Mediterranean Hardiness Rating H4 Foliage Evergreen, leathery aromatic leaves Flowers Inconspicuous, green When To Sow Or Plant March, April, September, October, November When To Prune January, February, December Easily recognisable by their fragrant, smooth, glabrous leaves, bay trees are evergreen trees or shrubs which are part of the flowering plant family of Lauraceae.1 Bay trees are native to the Mediterranean regions and can be used either fresh or dried in cooking.2 Why Grow Bay? The bay trees glossy leaves have been treasured for centuries and are now a firm favourite among gardeners. But, if you aren’t yet sold on this popular plant then allow us to break down exactly why we love them! Cuisine Bay leaves have a spicy, peppery, aromatic flavour and are commonly used in curries, soups and stews. It is also an essential ingredient in the herb mix ‘Bouquet Garni’. The leaves can be used fresh, or you can harvest them and summer and dry them. Dried bay leaves have a much more robust flavour but should be stored for no more than a year. Pest Resistance The plant itself is highly resistant to pests so can be used as a companion plant to help protect other plants from infestation. Dried bay leaves are also said to help to protect stored grains and beans and other foods from weevils. Privacy Because of the ease in which they can be clipped and trained, bay trees can be grown as a screen or a hedge to provide privacy and a shield from the elements. It is slow-growing, however, so patience is a virtue with this practical plant. Bay Tree Varieties There are only a few types of bay tree to choose from, which means narrowing down the right one for you is a piece of cake. Laurus nobilis This large, erect evergreen shrub is the bay tree most commonly cultivated, and its leathery leaves are used in cooking for its aromatic flavouring. The Laurus nobilis, or species bay tree, can grow up to 12m in height and over 8m in spread, but is slow-growing and can take up to 50 years to reach its full stature. It is traditionally clipped and trained into beautiful, ornamental topiary, providing sophisticated structure to formal gardens. It can also be used to create a hedge or screen, providing privacy to your garden. Because it is easily grown in pots and containers, it is a perfect addition to a garden of any size and can be grown both inside and out. L. nobilis ‘Aurea’ The L. nobilis ‘Aurea’, commonly known as ‘Golden Bay’, is a large evergreen shrub or, eventually, a small tree, growing to a maximum height of 8m. It sports attractive golden leaves which are particularly useful for providing winter colour, and these leaves can also be used in cooking. Growing in a broad, conical habit, this type of bay tree can also be trimmed and trained into stylish shapes and can also form smaller hedges. Like the L. nobilis, the golden bay can be grown either in the ground or in large pots or containers. L. nobilis ‘Angustifolia’ L. nobilis ‘Angustifolia’ is a rare shrub with slender, willow-like leaves which can also be used in cooking. Commonly known as a narrow-leaved bay tree, this species can also be clipped creatively into a work of art and grows well both in the ground and large containers. This variety is smaller and can reach an eventual height of around 6m and 5m in width, sometimes taller, although, as with the others, don’t hold your breath as this can take up to 50 years. How To Grow A Bay Tree Bay trees are wonderfully versatile and can be grown inside or out and in the ground or in containers. Planting Out If planting in the garden, choose a sheltered spot with well-drained soil, in full sun or partial shade. You can ready the soil by digging in compost and grit. If you are planting bay for formal structure, ensure that the young tree is standing straight to achieve the best aesthetic. Once planted, water well and continue to water regularly for a couple of weeks to help your bay establish itself. Container Growing If you are growing your bay in a container, then be sure to use tree and shrub compost, which usually contains loam for stability, and water well in summer when it is more likely to dry out. When growing bay trees inside, position it by a sunny window, avoiding exposure to drafts and heated appliances. Bay Tree Plant Care Bay trees are generally problem-free and easy to maintain; the most complex care comes if you are training it as topiary. Pruning Bay trees should be pruned in summer with secateurs, and old plants can be cut back hard in late spring to give them a new lease of life. Be patient with older plants as it can take them a while to get their vitality back, so you can prune them over two years by cutting half the stems back one year and the other half the following year. Top tip: If you are trying to train your bay tree as a topiary specimen for the first time, we highly recommend purchasing a topiary frame. This will help you sculpt your bay tree into your desired shape. For the best results, regularly prune through the growing season. Common Problems Bay trees are relatively trouble-free, but there are a few things to keep an eye out for. “Likely pests include bay suckers, which are psyllid insects, and scale insects, which cling tightly to stems,” shares Peter Lickorish, Master Horticulturist. “Pyrethrum can be used to treat sap suckers this, or nature can be used to solve your problems if you encourage ladybirds, using bug hotels, to predate pests.” In addition to pests, Peter notes how the climate can sometimes cause some problems for these trees: “Bay trees have suffered from the cold winter 2022-23 in the UK, with many showing browned leaves. “When dealing with frost damage, wait until active growth resumes and frosts are easing, around May, and prune out affected leaves, cutting back to the next healthy foliage. “Avoiding planting trees in positions facing east can prevent damage from rapid thawing after frosts. “Potassium, often found in fertilisers marketed for tomatoes, can act like anti-freeze and prevent some frost damage.” Harvesting Bay Leaves Bay leaves can be harvested throughout the growing season; however, if you wish to harvest a larger quantity, we recommend doing so in midsummer when the leaves are at their peak and have the fullest flavour. You can use the bay leaves fresh, or if you wish to dry them, place them on a baking sheet, spaced apart, so they aren’t touching and cover with a layer of paper towels. Place the leaves in a warm, dry location, out of direct sunlight. After a week, flip the leaves and leave them to dry for another week and voila! – your dried bay leaves are ready to go. No matter what size your garden is, there is always room for a bay tree, and they are an excellent choice for beginners hoping to hone their topiary skills. Whether they grow in the garden, or in pots, outside or inside, bay trees will reward you, year after year, with their beauty and deliciously flavourful leaves. References 1. S. (n.d.-e). Sweet Bay. Wisconsin Horticulture. Retrieved March 13, 2023, from https://hort.extension.wisc.edu/articles/sweet-bay-laurus-nobilis/ 2. Laurus nobilis. (n.d.). Kew Royal Botanic Gardens. Retrieved March 13, 2023, from https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:465049-1
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