Growing
Here's How To Take Geranium Cuttings - Buy Just Once And Propagate New Plants
IN THIS GUIDE When To Propagate Geranium Cuttings How To Take Geranium Cuttings 1) Take Your Cuttings 2) Preparing The Cuttings 3) To Wait Or Not To Wait? 4) Use Rooting Hormone 5) Potting Up Cuttings 6) Caring For Geranium Cuttings Benefits of Taking Cuttings References Bedding geraniums (Pelargoniums) are popular plants – by taking cuttings, you can buy just once and propagate new plants for your garden yourself each year. Pelargoniums, often called geraniums, are commonly used as annual bedding plants in beds and borders. They are also commonly grown in pots, on a patio or in another outside space, or even as houseplants inside a home. Difficulty Moderate Equipment Required Secateurs, gloves, pots, compost, rooting hormone (optional) When To Take Cuttings June, July, August There are many different types and interesting cultivars to choose from, and one thing that sets them apart is that, unlike most other annual bedding plants, it is very easy to take geranium cuttings and propagate your own plants at home. When To Propagate Geranium Cuttings This is a task best undertaken in summer, sometime between June and August. How To Take Geranium Cuttings If you are new to taking plant cuttings, taking cuttings from geraniums is not a bad place to start. These cuttings are relatively easy to take, prepare and care for. You will need a pair of scissors or secateurs, some pots and a small amount of compost or potting mix. You may also wish to use rooting hormone, though this is not always necessary. 1) Take Your Cuttings Make sure that you use well-cleaned, sterilised tools and make sure that the knife or other gardening implement is sharp. Begin by finding a fat, juicy and healthy stem on your geranium plant. Cut this off just above a bud on the parent plant. You should aim for cuttings that are around 10-12cm long. Repeat until you have a few cuttings to work with. It is best to start a few cuttings off at the same time, so you will still likely have some success even if not all of your cuttings make it through. 2) Preparing The Cuttings Once you have taken the material for the cutting: Immediately remove the lower flower buds and leaves. Leave just the stem over the lower half of each one. Trim the bottom of the cutting to just below a node. These nodes are areas of the plant which have a concentration of plant hormones, which thereby help rooting to take place. If there are any particularly large leaves on the upper portion of the cutting, you can also cut half of the leaf off to reduce moisture losses. 3) To Wait Or Not To Wait? Some gardeners will proceed to the next step immediately, getting their cuttings potted up as quickly as possible. However, some gardeners recommend leaving the cuttings to callus at the end before planting. This simply means leaving the cuttings on a piece of newspaper or paper towel for 3-5 days so that the end forms a protective ‘scab’ over the cut end. This can seem strange, and the cuttings will look like they have wilted, but they should perk back up when planted into pots. The benefit of leaving the geranium cutting to form a callus is that it can reduce the chances of deadly fungal infections like root rot and black leg, which are amongst the most common reasons why geranium cuttings fail. 4) Use Rooting Hormone To improve the chances that your geranium cuttings will root successfully, you can also consider dipping the bottom end into rooting hormone.1 This step is not strictly essential, as geranium cuttings may well root on their own. However, success rates will be higher if you use a rooting hormone.2 One thing to note is that you don’t necessarily need to purchase a rooting compound, you can also make your own. One common natural ingredient often used for this is willow: willow twigs are added to water to make a natural rooting aid.3 You can also dip the end of the cutting in apple cider vinegar, honey or cinnamon powder, for example, to increase the chance of cuttings rooting successfully and reduce the chances of fungal infections killing your cuttings before they root and grow successfully. 5) Potting Up Cuttings Next, take your cuttings and insert two or three around the edges of each small pot. Of course, you should prepare your pots and fill them with a suitable growing medium before you take your cuttings. Reused containers like yoghurt pots with holes pierced in the bottom can work well. The pots should be filled with seed compost or seed-starting potting mix, mixed with sharp sand to improve drainage. If you do not have a seed starting mix, and do not wish to buy one, use a light DIY (perhaps coir-based) soil-free potting mix (to avoid introducing pathogens), again mixed with grit for drainage. It is a good idea to place the cuttings around the edge, since around the edges of the pot they stand a better chance of remaining moist and rooting successfully. However, you can also simply place each cutting straight into its own individual pot. With geranium cuttings, it is best not to cover your pots, since this can encourage mildew to form on the leaves. Fungal infections can be more likely due to increased humidity. 6) Caring For Geranium Cuttings Positioning: Once you have placed the cuttings in the pots, water them and position the pots in a light, bright position indoors. Do not position them in an area of high humidity (like close to a kitchen sink, for example). Keep them somewhere relatively dry. Root Growth: Roots should begin to form within a few weeks. If you pull up a geranium cutting, you will see a thicker corky callus over the cut end, and small roots beginning to grow. After 6-8 weeks, a good root system should have begun to develop. If any cuttings wilt or turn black during this time, be sure to remove them right away, and dispose of them carefully, as diseases they harbour could spread to other plants. Watering: Make sure that you water your cuttings, but not excessively, as you take care of them over the winter months and into spring. Planting Out: In March or April the following year, remove the cuttings from their starter pots and pot each new plant up into their own individual pots of multipurpose potting mix/compost (or a homemade equivalent). Once all risk of frost has passed in your area, you can plant out your new geranium (Pelargonium) plants in your garden. Benefits of Taking Cuttings Taking geranium cuttings makes a lot of sense. Firstly, because buying annual bedding plants is not the most sustainable or eco-friendly thing to do. The plants you can purchase usually come in plastic pots, and we all know by now the terrible toll plastic takes on the environment.4 The pots also often come filled with a peat-based potting mix, or include synthetic fertilisers in the growing medium. Both peat extraction and synthetic fertilisers also come at a huge cost for people and planet. Wherever possible, if you want to be an eco-friendly gardener, you should try to grow organically, and propagate your own plants at home. Plants can be propagated through seeds, of course, and many perennials can be propagated through division. But cuttings – softwood, semi-ripe and hardwood are also key ways to make new plants using those you (or others around you) already grow. Taking cuttings from annual geraniums means you can get new plants, clones of the original plant, without having to buy new ones each year. As you can see from the above, taking your own geranium cuttings is pretty easy. And even if your cuttings don’t all take, you should have fairly high success rates if you follow the instructions above. So even if you have never taken your own cuttings before, don’t be afraid to give it a go. References 1. Zhang, W., Fan, J., Tan, Q., Zhao, M., Zhou, T., & Cao, F. (2017). The effects of exogenous hormones on rooting process and the activities of key enzymes of Malus hupehensis stem cuttings. PLOS ONE, 12(2), e0172320. https://doi.org/10.1371/journal.pone.0172320 2. Rooting hormones improve uniformity among vegetative cuttings. (2018, February 13). MSU Extension. Retrieved March 16, 2023, from https://www.canr.msu.edu/news/rooting_hormones_improve_uniformity_among_vegetative_cuttings 3. Home Made Plant Rooting Hormone – Willow Water. (2022, December 19). Deep Green Permaculture. Retrieved March 16, 2023, from https://deepgreenpermaculture.com/2010/12/15/home-made-plant-rooting-hormone-willow-water/ 4. Plastic pollution. (n.d.). Friends of the Earth. Retrieved March 16, 2023, from https://friendsoftheearth.uk/plastics
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Potted Peonies - 'Provide Plenty Of Space For Their Growth' Says Carol Adelman
IN THIS GUIDE Potted Peony Varieties Choosing Pots For Peonies Filling Your Pots Siting Peonies In Planters Planting Peonies In Pots Potted Peony Care Peonies are attractive, traditional cottage garden plants that can (contrary to some opinions) grow well in suitable pots. However, as deep-rooted plants, peonies do require deep pots or containers. They will be more challenging to grow in pots than in the ground. Remember, peonies are large and vigorous plants – and as with so many other plants, it will be far easier to grow them in beds or borders. But, you can still grow them in large pots if you are lacking in outdoor space. Potted Peony Varieties ‘Itoh’ Peonies Some peonies which are better suited to growing in containers include: Paeonia ‘Oslo” P. ‘Singing in the Rain’ P. ‘Dublin’ P. ‘Moscow’ P. ‘Border Charm’ P. ‘Bartzella’ P. ‘Gay paree’ P. ‘Magical Mystery Tour’ Choosing Pots For Peonies According to Carol Adelman, President of the Pacific Northwest Peony Society, providing plenty of space for peonies to grow is one of the most important factors when caring for these plants. “Provide plenty of space for their growth. The roots grow out to the sides. “Think of going to market and finding carrots with the tops on, then setting them down, all spread out in a circle. “That is how a peony root grows – out every side.” It is therefore best to start off peonies in a large pot that is at least 50cm deep and 50cm wide. As your peonies grow, however, you will of course have to think about transferring it to a larger container. It is likely that you will have to increase the container size every 3-4 years. Be sure to choose a pot which is able to drain freely, as peony tubers can rot in waterlogged conditions. Ensure that there are plenty of drainage holes in the base and that water can flow out of these freely. Filling Your Pots Peonies need a fertile and free-draining growing medium. A general-purpose peat-free compost or potting mix, ideally mixed with topsoil or loam-based, should be amended with horticultural grit or perlite to improve drainage. Remember that it will be important to keep the soil evenly moist throughout the growing season, but not boggy. Make sure you leave 2.5cm space as a minimum for water at the top of the container, above the growing medium and mulch which should be added on top. Siting Peonies In Planters Peonies in pots should be positioned in a sheltered spot, in full sun or partial shade. It is very important to think about how you will keep the plants protected from strong winds. And you should also be sure to think about the ease of watering when choosing where to place plants in pots. It can also be a good idea to consider other plants which bloom concurrently and which could look good grown in pots close to peonies in containers. Irises, Lavender, Salvias and Alliums are all good options to consider, for example. Roses might also be grown in pots close by. Planting Peonies In Pots Peonies are usually purchased either as bare-root specimens, to be planted out in late autumn, or as potted plants which are purchased and repotted in the spring. When planting peonies in pots, it is very important to plant them to the right depth. The crown of the plant should be no more than 2.5-5cm below the soil – planting too deep can reduce flowering. Be sure to mulch after planting with well-rotted organic matter. A homemade compost or well-rotted manure can work well. This mulch will add slow-release fertility, and prevent excessive evaporation from the soil surface, helping to reduce water needs. Be sure to leave a clear space around the crown and developing buds as these may otherwise be damaged or begin to rot. Potted Peony Care Caring for peonies in pots or other containers is not always easy. However, it can be relatively straightforward as long as you bear the following in mind: Support Some peonies benefit from staking, since they have larger flower heads and can sometimes struggle to hold these up without some support. Be sure to place supports in your pots when planting if these will be required for the cultivar or cultivars you are growing. Watering Peonies grown in the ground will typically require regular watering in dry weather over the first year as they become established – but they will not usually require regular watering in the UK on an ongoing basis. However, things are a little different when peonies are grown in pots, since containers will dry out far more quickly, and peonies’ deep roots will not be able to delve deep to seek out water. Though peonies like free-draining conditions and are relatively drought-tolerant, it is important to keep your growing medium moist throughout the growing season when growing peonies in pots. Feeding As well as providing a good quality organic mulch around your plants, you should also feed your peonies in pots at least once a year in spring with a good quality organic fertiliser. Experts suggest applying a spring peony fertiliser with an NPK of 10-4-18 (+ 2% MgO + 4% CaO). It can also be a good idea to feed peonies again after summer flowering with a fertiliser with an NPK of 11-5-12 (+1% MgO + 3% SO3). However, making your own organic liquid feeds (such as compost teas etc.) with less precise or scientific formulae can still yield good results. Deadheading & Cutting Back Most peonies are hybrids and do not set viable seed, meaning any seed that did set would not come true. So you will lose nothing by removing all dead flower heads after they have finished blooming. When the peony foliage dies back in autumn, it is best to cut the foliage at ground level. This should reduce the risk of peony wilt disease taking hold, which is a fungal infection – the main disease which impacts these plants. Winter Care Peonies tubers are usually left in the ground to overwinter in the UK when grown in beds and borders. They are fully hardy. However, when you are growing peonies in containers, they can be more vulnerable to freezing. They can also encounter problems with waterlogging over the winter months. If you would prefer not to unearth the tubers, you can protect pots with insulating materials wrapped around the sides and mulches over the top. Grouping containers together, and placing them close to materials (like stone or brick walls) or using pots with high thermal mass can also help prevent freezing. And placing the pot undercover or in the rain shadow of a wall can help reduce waterlogging issues that can lead to rot. You could also move the container (or just the tubers) into a cool space for overwintering, before repositioning or replanting them in spring. Division Peonies are long-lived plants and grow steadily. Over time, they can make large clumps, and after potting up over the years, you may find that they outgrow the largest suitable container which is practicable. Dividing mature peonies in late autumn will allow you to split your plant and repot sections into smaller containers, as well as giving the plant a new lease of life and boosting the blooms which may have begun to decline in number over time. New plants from divisions will be clones of the parent plant and they should bloom after a couple of years. “Division will be particularly important with container-grown plants because of the limited root environment,” shares Master Horticulturist Colin Skelly. “Division will keep the plants rejuvenated and provides the opportunity to refresh the compost at the same time.” Though growing peonies in pots can be a challenge, you may find it worthwhile to be able to enjoy these blousy, colourful blooms in your container garden. See our full peonies care guide for tips on planting them in the ground.
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Dividing Hostas: 'It Will Be Best To Dig Them Up Every 3-4 Years' Advise These Experts
IN THIS GUIDE Why Split Hostas? When To Split Hostas How To Divide Hostas 1) Pry Your Hosta From The Ground 2) Tease The Roots Apart 3) Create Smaller Divisions 4) Place Back The Parent Plant 5) Plant Out New Divisions Siting Hostas Hostas are incredibly useful plants to grow in your garden and knowing how and when to split them makes it easier to keep them healthy and increase your collection. They are a well-known ornamental shade plant, forming elegant clumps and sometimes reaching impressive sizes. This plant is commonly grown for its attractive foliage, which can come in a range of different hues and with variegation. If you have some shady or partially shaded spots in your garden, hostas can be an excellent choice. However, Horticulturist Peter Lickorish warns: “As with many perennials, clumps of hostas can develop a bare centre and patchy growth if not divided regularly. “If the clump is treated like a pie, slices of the pie can be lifted, each with only a small piece of the older, weaker central growth.” Why Split Hostas? “Most hostas, depending on the look you want, can live a long time without dividing,” says David Teager from the Delaware Valley Hosta Society. “They look best as big, mature clumps. However, if you wish to maintain a tidy edging of hostas, it will be best to dig them up every 3-4 years and divide them.” “Hostas generally grow to the space that you give them but you will have some varieties that will be stronger than others,” explains Ollie Walker from Sienna Hostas. “These may need dividing in order to give the slower-spreading varieties space.” Generally, hostas are split for two main reasons: 1) Preventing Overcrowding The first is to prevent overcrowding in perennial planting schemes and keep mature plants healthy. “If left undisturbed, giant hostas can reach a clump size of over 2m in diameter,” shares Sue, the Owner of Sue Proctor Plants. As Sue explains, hostas spread to form large clumps over time, and may outgrow the position in which they were initially placed. “Hostas can live with being overcrowded for quite a while but this can affect their mature dimensions,” says Melanie Collins, a Partner at Mickfield Hostas specialist nursery. “Many varieties, even small ones, can have a decent spread if they’re allowed to develop outside of the confines of a container.” When a hosta plant grows large, it can become crowded, and may reduce in vigour as it outstrips water and nutrient resources available. Other plants in the vicinity may also suffer when perennial plants in mixed plantings are not divided, as Robert Barlow from North Staffordshire Hostas explains: “Dividing hostas helps keep them more compact, allowing you to grow them in a specific garden space.” “Hostas are like any other herbaceous perennial; they effectively grow in size around the outside of the crown,” says the owner of Rewela Hostas, John Plant. “Eventually, the centre of the crown dies off. It is important to re-invigorate by splitting your hostas, which will also create younger, healthier plants.” 2) Propagating New Plants It allows you to propagate new plants – and is an incredibly easy and completely free way to do so. When you split hostas, you get free new plants to place elsewhere in your own garden, or to give, perhaps, to family or friends says John from Rewela Hostas. Dividing hostas and other existing perennial plants in your garden is also a more sustainable and eco-friendly solution when populating new beds or filling new garden areas. Since you will not have to purchase any new plants in plastic pots, you can reduce your negative impact on the environment. If you are new to plant propagation, then dividing perennial plants like hostas is a very simple, straightforward place to start. When To Split Hostas “If you want to divide Hostas, they can be divided at any time during the growing season, but it is usually best to do your dividing between the spring and early autumn, especially when dividing miniature hostas,” explains Barry Ankney from the American Hosta Society. Summer-flowering plants more broadly, including hostas (even when flowers are not produced on all cultivars), are best divided in spring (March to May) or in the autumn (September to November) because water is generally more accessible in the soil, and cooler temperatures reduce plant stress. “Dividing your hostas is best done in spring when the pips are just emerging,” David suggests. If the autumn is particularly wet, it may be better to delay division until the spring to reduce fungal problems and prevent plants from rotting. You can also split hostas over the summer, but the strain on the plants will be increased during hot and dry weather, so consider thinning a third of the foliage. How Often Should You Split Them? You can split mature hostas to make new plants any time after an existing clump is well-established. For health and to prevent overcrowding, you will usually split hostas every 4-5 years. Hostas grown in containers may obviously outgrow their containers and need to be split more frequently as Robert shares: “Hostas grown in pots should be divided every 3-5 years. “You can tell when this needs to be done from all the new shoots that appear to be growing around the edge of the pot.” How To Divide Hostas “Dividing hostas is easy but can require some strength,” says Melanie. To uproot and divide a mature clump of hosta: 1) Pry Your Hosta From The Ground “Our main tip for division is to disinfect tools between each plant, as this is a prime opportunity for diseases to be spread,” warns Ollie. Remembering this, use a clean garden fork or other implement to gently pry the clump up from the ground or its container. Try to retain as much of its root system as possible and avoid dividing plants in the middle of the day, when soil is often drier. Gently shake off excess soil so that you can see the root system more clearly. 2) Tease The Roots Apart Carefully tease the roots apart with your hands to separate them into sections. This is usually rather easy with a plant that has fibrous root systems like hostas. “The natural breaks made by pulling, rather than slicing, plants apart often heal better,” advises Horticulturist Peter Lickorish. You should not need to use a spade or other sharp implement as you will do when dividing more woody-rooted perennials (though you can use one). However, John Plant suggests that there is no strict method for this: “Don’t be afraid to tackle splitting with whatever it takes. This may be done by using a spade, or by simply pulling it apart.” You may simply wish to split the clump in two, replanting one section and finding space elsewhere for the other. Alternatively, you can opt for a slightly different method of division: “Personally, I like to divide the plant by removing a portion of the plant from the ground, as this requires minimal disturbance of the entire plant,” says Barry Ankney. “I like to tie back the foliage with bungee cords to open up the centre of the plant. I can then take a garden spade and cut directly down through the centre of the clump. “Then, using a garden fork, I dig a portion of the plant. One section then can remain in the ground, with less disturbance to its root system. “The portion I remove can be replanted in a new location as a clump or can be further divided into smaller clumps before relocating.” 3) Create Smaller Divisions If you are interested in making new plants, you might separate the clump that is not to be replanted into a series of smaller divisions. “It is often suitable to dig each clump, divide into thirds and plant only one piece back in the original hole (amended with some nice compost),” says David Teager. “Then you have two pieces to share, making hostas live up to their nickname as the friendship plant.” If you do this, make sure each section has some roots (as much root system as possible) and a minimum of 1-3 good buds in the above-ground portion of the plant. 4) Place Back The Parent Plant Replant the division that will remain in place, carefully placing it back into the soil and firming the soil around it, ensuring it is planted at its original depth. Mulch around it with organic matter. “Some spreading (rhizomatous) hostas can simply be tidied up by digging around the edges if they get too big for their space,” says David Teager. “Newly planted divisions could be mulched with wool pellets, which can help to deter slugs, especially early in the spring when soft new shoots are simply irresistible,” says Peter. 5) Plant Out New Divisions Plant out or pot up the portions you have split from the parent plant as soon as possible, taking care to make sure they do not dry out. “Hostas that are divided often take several years to recover to their mature size,” warns Barry. Once you have replanted the parent, or settled it back in place, you can turn your attention to the new plants you have made. You can replant hosta divisions in pots or containers, or replant them right away into another part of your garden, but make sure you choose the right sized location, says Melanie: “Often people put large varieties in too small a container and wonder why their plant seems to get smaller every year when they simply need more root room.” Be sure to keep your hostas well-watered, especially until they become established. Choosing a deeper pot can help keep the large, fibrous roots keep moist and gives them better space to grow, according to Peter. And remember that they will require more water when grown in containers, or when placed in full sun. Siting Hostas Remember that while some hostas can be placed in full sun, most will prefer a moist and somewhat shady site. They can work very well in the dappled shade below fruit trees, and are an interesting edible ground cover option to think about for a fruit tree guild or forest garden. Hostas can work well when grown in mixed planting schemes beneath an apple tree, for example. Peter Lickorish advises contrasting their large leaves with plants with slender stems or longer, thinner foliage. You might also grow hostas in a shady perennial border. It can work well both in ornamental schemes and in beds or borders with other perennial vegetables and herbs. Learning how to split hostas does not take a lot of effort. As you can see from the above, it is an easy process, which will allow you to keep existing plants happy and healthy, and get more of these useful plants for your garden.
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Beware Delphiniums Sensitive Root Systems Before Growing In Pots Says Graham Austin
IN THIS GUIDE Best Container Varieties Container Positioning Container Types Growing Medium Sowing and Planting Container Delphinium Care References Delphiniums usually do best when planted in the ground but they can also be grown in suitable containers. One challenge when growing delphiniums in pots is that they have sensitive root systems and very much dislike overcrowding. Another challenge is that these plants can grow rather tall, and so can be vulnerable to falling over, or being toppled by strong winds, as Home Farm Plants owner & delphinium specialist Graham Austin shares: “When grown in containers, it is important to make sure that the pot can drain well, as delphiniums hate sitting wet. “Staking still needs to be done, but you should be careful, as the pots can blow over if placed on a patio or another hard surface”. However, if you make the right decisions, they can look spectacular in a container garden, and some may even be suitable for attractive cut flowers. There are two main types of delphinium grown in UK gardens, and both can potentially be grown in pots or containers: The first type is perennial delphiniums, which flower in early summer and come back year after year. Some are very tall – over 2 metres – but there are also smaller cultivars that work well in pots. The second type is annual delphiniums, also known as larkspur. These are annual crops, and so flower only for a single season. But their flowers will bloom throughout the summer months and since they are smaller, they may be easier to grow in pots. Best Container Varieties If you decide to grow perennial delphiniums, then it is a good idea to opt for the Magic Fountains series. ‘Magic Fountain’ Delphinium These are smaller delphiniums that will grow to an eventual height of 75-90cm tall, and spread to create clumps of 0.1-0.5m. There are a number of different colours within this range that you can choose from. If you decide to grow annual delphinium, or larkspur, you might consider: Delphinium grandiflora Delphinium ajacis These are easy to grow from seed and are a cheap and cheerful way to fill your patio containers, window boxes or even hanging baskets. They tend to be a little tougher and easier to care for than their perennial cousins. “Species like Delphinium grandiflora retain flowers that have not been cultivated to have larger, often double, flowers,” shares Colin Skelly. “They therefore have the dolphin shape that gave the genus its name – from the Greek for Dolphin: delphis.” Container Positioning Both perennial and annual delphinium like a sunny and sheltered position. It is important to think carefully about the best place to position your potted plants so that you can maintain them easily, and also so that they are not damaged by wind. Be sure to think about sunlight and shade, prevailing wind direction and also about the water needs of your plants and how you plan to meet them. Also consider other plants in your garden – as well as man-made structures and how these affect conditions. You might grow delphiniums in their own containers, or in larger containers as part of mixed planting schemes. Even when plant roots do not have the chance to communicate, you should still think about how each container plant you choose works in relation to the other plants, and the wildlife, in your garden. Container Types Containers for delphiniums, especially taller perennial types, should be heavy and stable. Even in a sheltered spot, it is important to make sure that any pots and containers you choose will not tip over with tall plants like delphiniums within them. Remember to choose a pot of sufficient width and depth to accommodate your plant(s) and pot up as necessary until you have your delphiniums in a suitably large container. Delphiniums do like moisture during dry periods, but it is also important to create free-draining conditions in a container. That means choosing a container that has good drainage holes at the base; it may also be beneficial to raise containers up off the ground so water can always drain out freely. Growing Medium As well as requiring a moist but free-draining growing medium, delphiniums are also hungry plants that will require plenty of nutrients. For this reason, it is important to choose a fertile growing medium. Choose John Innes No. 2, or any good quality multi-purpose peat-free compost with added John Innes, or another loam-based mix. Add grit added to improve drainage, and place crocks at the base of the pots. Sowing and Planting Perennial delphiniums are usually purchased as plug plants in spring, or as potted plants in summer ready for planting out. There are also seeds available for sale, but not all cultivars of perennial delphiniums can be propagated from seed. Plant out these types into your containers in spring or early summer to give them the best chance. However, you can plant out at any time as long as you ensure adequate water and the growing medium is not waterlogged or frozen. Replant at the same level as the plants were at in their previous pot, and water in well. Annual delphiniums (like some perennials) can be grown from seed. The seeds can be sown in spring or in autumn for earlier flowering, then potted up in spring and placed into their containers for blooms over the summer months. Container Delphinium Care Plant Support Some varieties will require support. It can be a good idea to insert canes or stakes into the soil in your containers, and to tie in the delphiniums to these supports as they grow. Watering “Watering may be required more often during the growing season for potted delphiniums”, says Graham. Delphiniums will need to be watered during dry periods over the summer months – remember, watering is more crucial, and more frequent, with container-grown plants. Keep the growing medium moist but not damp or soggy. With perennial types, remember to reduce watering as temperatures cool, and over the winter if you are overwintering your plants. Feeding Delphiniums need good fertility. One important step to maintain that fertility is adding a good quality organic mulch to the top of the pots or containers that you choose. When growing in containers, it is also a good idea to add an organic liquid feed regularly over the summer months. Choose one that is rich in phosphorus and potassium and avoid adding too much nitrogen as this can encourage leafy growth at the expense of flowers.1 Deadheading Perennial delphiniums should be cut back after flowering and annual types should be deadheaded to prolong the summer flowering display. Just remember to leave some to set seed if you wish to collect your own seeds for next year. Overwintering Perennial delphiniums in pots should be moved undercover or into the rain shadow of a wall in winter to prevent waterlogging. Delphinium expert Graham also recommends adding a layer of horticultural grit to your container-grown plants in the winter for extra protection from winter cold and wet. Repotting, Propagation & Division Re-pot delphiniums before they become too crowded, and divide perennial delphiniums every 2-5 years. Of course, dividing mature clumps is one way to obtain new plants. You can also take cuttings or raise from seed as mentioned above. Pests and Problems Delphiniums are very attractive to slugs and snails, so be vigilant for these pests. Make sure you protect your potted plants and attract plenty of slug and snail predators to your garden to keep their numbers down. Powdery mildews can also be a common issue. Avoid overcrowding, and under watering, to reduce the chances of issues like this taking hold.2 But delphiniums, when cared for correctly, are usually relatively trouble-free plants. They are often much easier to grow in the ground, but where there is not space, growing them in a container garden can be a good idea. For more detailed growing advice see our delphinium plant care guide. References 1. Doubrava, N. (2022, August 8). Why Plants Fail to Flower or Fruit. Home & Garden Information Center | Clemson University, South Carolina. Retrieved March 15, 2023, from https://hgic.clemson.edu/factsheet/why-plants-fail-to-flower-or-fruit/ 2. Delphinium-Powdery Mildew. (2022, May 17). Pacific Northwest Pest Management Handbooks. Retrieved March 15, 2023, from https://pnwhandbooks.org/plantdisease/host-disease/delphinium-powdery-mildew
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Pieris Can Be Left Alone, But Follow These Steps If You Decide To Prune Yours
IN THIS GUIDE Pieris Can Be Left Alone Why Prune Pieris? How to Prune Pieris Simple Maintenance Pruning Hard Pruning Deadheading Maintaining Shape and Size When To Prune Pieris Post-Pruning Care Pieris are useful evergreen shrubs for your garden, but understanding their care includes learning how and when to prune. One of the reasons that Pieris is such a popular garden plant is that it is a great low-maintenance option for your garden. Pieris japonica and ‘Forest Flame’ are two incredibly popular shrubs in the UK and neither requires too much effort from gardeners. One job that you might like to think about each year, however, is pruning your plant. Pieris Can Be Left Alone Pieris shrubs may not necessarily have to be pruned at all. If you are happy for them to grow more naturally and grow to their full potential, you can more or less leave them to their own devices if you prefer. If you are a proponent of natural gardening then this may be the approach you decide to take. Pieris is usually only ever pruned lightly, and this is often more for the sake of appearances than for the health of the plant. Why Prune Pieris? Leaving your Pieris largely unpruned can often be the best choice for wildlife, and if you do decide to prune your Pieris, less is usually more. However, pruning Pieris shrubs correctly can sometimes be beneficial. It can allow you to maintain their shape and size, and deadheading after flowering might not be strictly necessary, but it will often be a good decision for the appearance of your garden and may make new foliage even more impressive and spectacular. You might prune Pieris: Simply to remove dead, damaged or diseased material if there is any. Because it has grown large and has outgrown its location. To improve its shape and form if it has become lopsided or unappealing aesthetically. To gently restrict its growth and keep it in check. To remove dead flowers to keep your garden looking neat. How to Prune Pieris Pieris falls into RHS pruning group 8, which includes early flowering evergreens. Simple Maintenance Pruning Most of the time, Pieris will only require pruning to remove any dead, damaged or diseased material. Take a good look at your shrub and aim to take out anything which seems to have any problems with a clean, sharp pair of secateurs, loppers or another pruning tool. Often, this will be enough. Hard Pruning If your Pieris is very large and overgrown, you can undertake hard pruning to rejuvenate it entirely, by cutting out around 1/3 of the old wood and, if necessary, cutting back hard to the required size and shape. Hard pruning will likely lead to loss of flowering the following year, and perhaps the year after that. However, the flushes of new colour and the size restriction can mean that this is still a good bargain. And Pieris, though they do not regularly require it, do tend to respond pretty well to hard pruning if they are otherwise healthy and in the right location. Another thing that you might consider with a mature and large Pieris is pruning it into a standard form (making it look more like a tree than a shrub). With some types of Pieris, you may be able to remove lower stems around the main trunk, starting at the ground and working upwards, to turn it from a shapeless shrub into a more attractive garden feature. So this is something else to consider for a mature and currently unappealing Pieris shrub. Deadheading You may also wish (largely for aesthetic reasons) to deadhead your Pieris, even if you do not need to do any other pruning. Removing flowers as soon as they have faded can help keep flowers coming. And when the plant has finished its blooming period and the later flowers are beginning to go to seed it can keep your shrub looking neater and more appealing. Simply snip off each of the spent flowering stems to a healthy bud. Do not confuse the flowers for the colourful young leaves. One thing to note however is that deadheading is not really necessary – if you leave the flowers in place, they will usually fall off of their own accord. And deadheading and being too neat and tidy in your garden is not always, in general, the best thing to do for wildlife in your garden. However, deadheading may also help plants focus on creating beautiful new foliage growth. It is also worth noting that Pieris are usually grown mostly for their attractive foliage rather than for their flowers. Maintaining Shape and Size At the same time as deadheading after the flowering period, you can also trim branches lightly here and there to maintain a desired shape and size. Just make sure that you do not cut into too much of the new growth which will produce next year’s blooms unless you have decided on hard pruning. When To Prune Pieris Since Pieris are in pruning group 8, they should always be pruned immediately after flowering, in spring. Most Pieris will bloom between March and May. So May or early June is a good time to prune in the UK – and also a good time to take any cuttings for plant propagation. Like other shrubs in this group, they require little pruning and as mentioned above, you may not need to do much pruning at all. Certainly, it is important to avoid pruning Pieris after the end of the summer, since this can spur new tender growth which can be damaged by frost and cold temperatures in winter. Post-Pruning Care Pieris with mulch Pruning correctly does not end with cutting off the plant material. After pruning your Pieris, you should also take care of it by adding a good quality organic mulch. Replenishing a layer of leaf mould, compost or well-rotted manure, or other organic material each spring will make sure there are plenty of nutrients for the shrub to uptake throughout the rest of the growing season. “If you have a pine in your garden or somewhere nearby if you can get permission, collect the needles and use these to mulch your Pieris,” advises Colin Skelly, a Horticultural Consultant. “Repeated annually these can be a great way to maintain a low soil pH and soil moisture as well as to suppress weed germination.” You should also think about feeding your Pieris (especially if growing in a pot or container) with a good general-purpose organic liquid fertiliser (a homemade compost tea, for example). This will give plants a boost after pruning and help make sure they respond well to the pruning with healthy new growth.
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Why Growing Magnolias In Pots Allows You To Easily Meet Their pH Requirements
IN THIS GUIDE Can Magnolia Trees Be Grown In Pots? Potted Magnolia Varieties Positioning Potted Magnolia Choosing Containers For Magnolia Potting Mix For Magnolia Planting Magnolia In Pots Caring For Potted Magnolia You might think of Magnolias as a plant for larger gardens, but some can be grown in pots. In this article, we will talk about which magnolias to grow in pots in a container garden, and the choices you will have to make to keep them healthy and happy. Can Magnolia Trees Be Grown In Pots? In short – yes! If you grow magnolia trees in the ground, you will obviously be able to choose from a wider variety of plants, and they will take a lot less work. Container gardens are generally higher maintenance for the gardener. However, there is one very good reason why you might wish to grow Magnolia in containers, and that is because of their pH requirements. Magnolia trees like neutral or acidic soil conditions. While some can cope with more alkaline conditions, if you have very alkaline soil, it is often best to grow Magnolias in containers rather than fighting to amend the pH and grow them in the ground. Fortunately, magnolia trees have rather shallow roots, which can make them a good candidate for growing in larger containers. Some types have fragrant flowers which makes them great for positioning in pots close to a seating area or outdoor leisure space. Potted Magnolia Varieties M. stellata ‘Rosea’ Magnolia trees can be full-sized trees or larger shrubs. If you plan on growing Magnolia in a container then it is important to choose the right variety. Those with smaller forms and less vigorous growth habits are generally easier to grow in pots. Some options to consider which can be good for container gardening include: M. ‘George Henry Kern’ M. ‘Susan’ M. stellata ‘Jane Platt’ M. stellata ‘King Rose’ M. stellata ‘Royal Star’ M. stellata ‘Rosea’ M. denudata ‘Sunrise’ M. denudata ‘Yellow River’ M. x loebneri ‘Mag’s Pirouette’ M. x loebneri ‘Merrill’ M. x loebneri ‘Merill’ Make sure that you understand how large the Magnolia you are considering will eventually grow, and remember that while some Magnolias can be grown in containers, not all can. Even those which are good for container growing will need a sizeable pot and the right conditions to thrive. Positioning Potted Magnolia Magnolias, whether grown in the ground in a garden or in pots, will require a site that is as sunny and sheltered as possible. Magnolias are actually usually pretty hardy in the UK, however, the flowers of magnolias can easily be damaged by early spring frosts. Choosing Containers For Magnolia Magnolias are usually purchased as pot-grown trees, though they can come in a range of containers of different sizes. It is best to repot your Magnolia as soon as it arrives into larger, heavy containers which can support the weight of a small tree or shrub and which will not tip over easily. You can purchase containers, but there is also a range of reclaimed items you could consider. Remember to choose a container that will not dry out too quickly during the summer months. Inadequate water over the summer is one of the common reasons why a magnolia might not flower as expected. Remember that a black or dark-coloured container will heat up and dry out more quickly. The material from which a container is made is also important – glazed pots are better than terracotta for water retention, for example. It is also important to make sure that your container has drainage holes and allows for good drainage too. Magnolia trees grow root systems very quickly and intricately, so it is important to choose a container that will suit the ultimate size of your tree. Look at the girth of the trunk to get an idea of how wide the container needs to be. A Magnolia with a trunk that is 2cm wide, you will need a container at least 60cm wide and 60cm tall. For each centimetre around the diameter of the trunk, the container should be 30cm wider and taller. So if a mature magnolia tree trunk is 5cm around, it will need a container or planter 1.5m wide and 1.5m tall. Larger containers will be needed to grow Magnolia to maturity in pots. Potting Mix For Magnolia As mentioned above, Magnolias can thrive in neutral or acidic soils. Many magnolias will grow perfectly well in a general multi-purpose compost with added John Innes (or a homemade equivalent). However, certain varieties will thrive in more acidic conditions and so it can sometimes be beneficial to fill your pots for Magnolia with an ericaceous potting mix. Whichever potting mix you choose, make sure it is light and free-draining, yet moisture retentive, to keep your magnolia tree as healthy and happy as possible. Planting Magnolia In Pots When you are planting a magnolia into its new pot or container, it is important to take care not to damage the root system as you do so. As is usual with trees and shrubs, it is important to make sure that you bury the magnolia to the same level that it was in its previous pot. Make sure the graft point is not below the surface of the growing medium. After planting, water well around the base of the plant, and top the growing medium in the container with a leaf mould or another good quality organic mulch. This will help to retain water in your pot and stop weeds from growing up as much around the base of your tree. Of course, it will also help add fertility, providing nutrients as the materials decompose slowly over time. Caring For Potted Magnolia Watering Remember that a magnolia grown in a container will need to be watered more frequently in dry weather than one which is grown in the ground. Keep the soil moist throughout the summer months to keep magnolias healthy and flowering well. “Ideally water in the morning when plants begin to use it, although evenings are also okay,” advises Colin Skelly, an RHS Master of Horticulture. “To ensure that water is available to the plant throughout the pot soil, watering thoroughly less frequently is better than frequently but less thoroughly.” Feeding Magnolias grown in the ground will typically require only mulch, and will not need additional feeding. When grown in pots, however, some additional liquid feed may be helpful. Feeding magnolias grown in containers in early spring with a high phosphorus and potassium liquid feed can promote healthy growth and encourage more abundant flowering. Pruning Magnolias should only be pruned lightly, and after flowering. Remove any branches which are dead, damaged or diseased and any which are crossed and rubbing against one another. You can also prune to restrict size somewhat, but should be circumspect as these trees do not like or respond well to hard pruning. If you prune too much, flowering may be reduced or cease the following year. As long as you choose the right magnolias, place them in the right containers, with the right potting mix, in the right location, growing magnolia in pots is not too much of a challenge. Just make sure you do not let them dry out. Replenish mulch to add fertility each year, and your magnolia tree should be content in your container garden for many years to come.
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Caterpillars On Your Roses? This Is How To Deal With Rose Sawfly Effectively
IN THIS GUIDE What Is Sawfly? Large Rose Sawfly Identifying Large Rose Sawfly Leaf-Rolling Sawfly Identifying Leaf-Rolling Sawfly Rose Slugworm Sawfly Identifying Rose Slugworm Sawfly Infestation Solutions 1) Live & Let Live 2) Embrace Natural Predation 3) Remove Larvae By Hand 4) Organic Pesticides References If you see caterpillars on your roses, and some damage to your plants, sawfly species could be the culprits. Read on to learn more about the sawfly larvae you may encounter on roses in the UK, and how to deal with them if you find some in your garden. What Is Sawfly? Sawflies are insects in the Hymenoptera genus (the same group as bees, wasps and ants).1 The adults are winged insects that look like flies, and they have caterpillar-like larvae which feed on the leaves of plants – including wild and cultivated roses.2 There are several different types of sawflies that you may see the caterpillars or larval forms of on your roses.3 Large Rose Sawfly One of the sawfly types which can attack roses in the UK is the large rose sawfly. There are actually two species of large rose sawfly in the UK – Arge pagana and Arge ochropus.4 The former species is more common – the caterpillar-like larvae of these species can cause extensive leaf loss in early and late summer. Identifying Large Rose Sawfly You may see female sawflies dangling from stems by their egg-laying organs. The larvae hatch in groups between May and October, and feed together. Many leaves where they eat will be destroyed entirely. Leaf-Rolling Sawfly Another species of sawfly is the Rose leaf-rolling sawfly, Blennocampa phyllocolpa. This species inserts eggs into leaflets on rose bushes in spring and when doing so, secretes chemicals that cause the leaves to tightly roll-up.5 Identifying Leaf-Rolling Sawfly The damage done by these sawfly on rose bushes is distinguished by the tightly curled leaves. As mentioned above, this is caused by chemicals excreted when the females lay their eggs. The leaf rolling will usually occur between late April and early June. The larvae feed inside the rolled leaves, which can remain on the plant throughout the summer months. The larvae will go down into the soil in late June/July to overwinter and pupate in the spring. Rose Slugworm Sawfly Another species of sawfly that can cause issues for roses in your garden is the slug sawfly, or slugworm: Endelomyia aethiops. The larvae of this species nibble away the surface of leaves until all that is left of each leaf is the epidermis. Identifying Rose Slugworm This species does not cause defoliation. Rather, you will see ‘window-paning’ where the leaves have been eaten down to the epidermis and damaged areas turn white or pale brown. Larvae hatch as small, black slug-like creatures and develop into pale yellow-green larvae with light brown heads. The bodies are see-through and you can often see gut contents as a dark green line down the body. There are two or sometimes three generations each year, between June and October, though the worst damage is usually apparent in July and August. If you’re experiencing issues with your rose plants that don’t match the symptoms above, you should also check for rose black spot. Sawfly Infestation Solutions Though sawfly can damage the foliage on your rose bushes, it is important to note that if your roses are otherwise healthy and in good condition, they should be able to stand some damage or defoliation. Sawfly will therefore rarely kill your roses unless they appear in dramatic numbers. Keep your roses as healthy as possible, with healthy soil, companion planting, good watering where needed, and a pruning regime appropriate to the type of rose you are growing. Growing healthy plants is always the first step in effective organic pest control. Some good companion plants for roses include Foxgloves, Erysimum, Alliums, Salvias, Nepetas, Hyssop, Lavender… to name but a few. It is always best for pest control and biodiversity to grow roses among and alongside other plants in mixed polycultures, rather than on their own in dedicated beds. 1) Live & Let Live If you only have a light infestation, even of the large rose sawflies which cause the most extensive damage, you can simply tolerate them. Often, in an organic garden, it is best to take a live and let live approach. While sawflies can be horticultural pests, it is important to remember that like all native wildlife, they play an important role in the ecosystem. “The practice of tolerating damage to plants as necessary to supporting garden ecosystems is now mainstream,” shares Horticultural Consultant Colin Skelly. “I recently saw a leaf-rolling sawfly on several roses at an RHS garden and signage let visitors know that this was being accepted rather than treated, as roses are habitat in a garden food web.” The adult sawflies are pollinators, feeding on pollen and nectar amongst other things. And sawflies and their larvae also play an important role in the food chain and are eaten by a wide range of useful garden species. So as with most garden pests, it is not a good idea to try to eradicate them entirely. It is also important to note that if you try to eradicate a species entirely, this weakens the ecosystem, and their numbers can rebound dramatically, without being checked by other species in the ecosystem. 2) Embrace Natural Predation An an organic gardener, it is always important to embrace natural predation. By encouraging creatures that eat sawfly and their larvae to your garden, you can help keep their numbers down and keep your roses safe from damage. Wrens and other garden birds, and ground beetles, are useful predators for sawfly to welcome to your garden. Ladybird larvae will also sometimes predate sawfly larvae and so are another beneficial creature to have around.6 Make sure you have biodiverse planting, and other features, to keep them happy in your garden. 3) Remove Larvae By Hand It is important to remain vigilant and to check over your rose bushes regularly for any sign of infestation. The sooner you spot a problem, the easier it will be to deal with. In a garden, a vigilant gardener will often be able to spot a sawfly infestation early. Where the infestation looks as though it may become a problem, it is often possible to squash eggs or remove a small number of larvae by hand. Either dispose of the larvae, give them to chickens if you keep them in your garden, or leave out the despatched larvae on a feeder for garden birds. 4) Organic Pesticides In cases of extreme infestation, it may not be possible to pick off the larvae by hand. In such cases, you might consider an organic pesticide – contact insecticides containing natural pyrethrins can work, though you will usually have to repeatedly apply for good control. Remember, however, that even organic pesticides should only ever be considered as a last resort. Note: you should never spray roses while they are in flower, since this endangers bees and other pollinating insects.7 It is always best to look to natural pest control methods – holistic or integrated pest management – to keep your garden ecosystem in balance. References 1. The Editors of Encyclopaedia Britannica. (1999b, May 4). Sawfly | insect. Encyclopedia Britannica. Retrieved March 23, 2023, from https://www.britannica.com/animal/sawfly 2. Sawflies. (n.d.-c). Iowa State University. Retrieved March 23, 2023, from https://hortnews.extension.iastate.edu/sawflies 3. Sawflies. (n.d.-d). NatureSpot. Retrieved March 23, 2023, from https://www.naturespot.org.uk/gallery/sawflies 4. Large Rose Sawfly. (n.d.). NatureSpot. Retrieved March 23, 2023, from https://www.naturespot.org.uk/species/large-rose-sawfly 5. Pests and Diseases. (2023, February 22). Peter Beales Roses. Retrieved March 23, 2023, from https://www.classicroses.co.uk/blog/post/pests-and-diseases 6. Biological control in the home garden. (n.d.). Royal Horticultural Society. Retrieved March 23, 2023, from https://www.rhs.org.uk/prevention-protection/biological-control-garden 7. Finneran, R., Smitley, D., Elsner, E., Landis, J., Shrewsbury, P., Herms, D., & Palmer, C. (2019, May 1). Do not spray pollinator-attractive plants with insecticides when open flowers are present. Pollinators & Pollination. Retrieved March 23, 2023, from https://www.canr.msu.edu/news/do-not-spray-highly-attractive-plants-with-insecticide-before-or-during-flowering
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Why Hydrangea With Relatively Compact Shrub Forms Are Best For Growing In Pots
IN THIS GUIDE Container Hydrangea Varieties Placing Potted Hydrangea Choosing Containers For Hydrangea Container Potting Mix Potting Up Hydrangea Potted Hydrangea Care Most hydrangea can grow perfectly well in pots, though dwarf varieties are better suited. In this article, we will tell you everything you need to know to grow hydrangeas in pots or containers with good results. Read on to find out more about making the right initial choices, planting up your hydrangea, and caring for your potted hydrangea over time. Container Hydrangea Varieties The first thing to think about if you are considering growing hydrangea in pots is which type of hydrangea you would like to grow. Hydrangeas can be climbing plants, or shrubs. Those with relatively compact shrub forms are best for growing in pots. Some good compact hydrangeas to consider growing in pots include: H. macrophylla ‘Masja’ H. macrophylla ‘Paraplu’ H. macrophylla ‘Mini Penny’ H. ‘Miss Saori’ H. ‘Selma’ H. paniculata ‘Early Sensation’ H. paniculata ‘Little Lime’ H. paniculata ‘Bobo’ H. serrata ‘Shojo’ H. quercifolia ‘Sike’s Dwarf’ These are just some of the options to consider. You might also choose to grow climbing hydrangeas such as the evergreen H. seemannii in pots, as long as these are positioned correctly, and of sufficient size and stability. Remember to consider the colour and type of foliage and flowers that you would like from your hydrangea, since one varietal can look very different to the next. Of course, it is also important to consider where you would like to place your hydrangea in pots since this will also be vital in determining which type and cultivar of hydrangea to grow. Placing Potted Hydrangea Hydrangeas in pots can be placed in a range of different locations. You might place them on a patio or decking area, beside a doorway or window, or in rows of container shrubs to create division between different parts of your garden. Hydrangea are hardy and versatile shrubs that can work in many different garden settings – from spaces with a traditional cottage garden feel, to much more modern, contemporary designs. Most hydrangeas will do best in an area of partial shade or full sun. Most will not flower as well in deeper more pronounced shade. A west-facing spot could be ideal as most hydrangeas seem to thrive where they have shade in the morning followed by sun in the afternoon. However, one important thing to consider is that you do not want to place hydrangeas in pots in an area where they will dry out too quickly. Not providing enough water is one of the most common reasons why problems creep in when people grow hydrangeas in pots. Hydrangeas, no matter which type, tend to like to be grown in relatively moist conditions. “In the summer months, even large pots will need watering regularly to ensure that the soil moisture is sufficient,” shares Master Horticulturist Colin Skelly. “The most efficient way to water is through a drip irrigation system if this is possible, preferably with a moisture sensor. “Provide regular top-ups and check the soil moisture every night (pushing your finger into the top 5-10cm of soil). “If it is dry to 5cm or below, water more thoroughly, allowing it to soak away, then reapply.” Choosing Containers For Hydrangea Once fully grown, a hydrangea will typically require a large container, such as a half-barrel, trough, or another large reclaimed item. However, it is not usually a good idea to take a small hydrangea purchased in a pot and plant it up into a large container right away. This is because waterlogging can be an issue where there is excessive space around the plant roots. Choose a container that is just a little larger than the pot in which it came. Alternatively, choose a large planter or container and place a hydrangea in it alongside some other perennial plants which enjoy similar conditions, before thinning, pruning and transplanting these to new containers once the hydrangea grows. Make sure that you choose a pot or container which is relatively good at retaining moisture, and yet which has drainage holes at the base to allow excess water to drain through. Make sure that the container is heavy and sturdy enough to support the size and weight of your shrubs, and that it will not blow over or be toppled easily. Container Potting Mix Hydrangeas are not particularly fussy when it comes to the potting mix or medium in which they are grown. A general-purpose, loam-based potting mix is generally best. Hydrangeas can grow in mixes with a range of different pH levels. However, remember that if you are growing a blue type, you will need to choose an ericaceous compost, and maintain acidity over time. Potting Up Hydrangea The best time to purchase and pot up hydrangea into their new containers is either in spring or autumn, when the soil is warm and moist and transplantation will go smoothly. However, you can buy and pot up hydrangea at any time over the summer – as long as you make sure that the conditions are moist and that you keep watering consistently until the shrub becomes established. Take care not to place your hydrangea deeper in its new container than it was in its original pot. Water the shrub in well, and then be sure to mulch around the top of the new container – leaf mould is ideal, though you can also use a homemade compost or well-rotted manure. For hydrangeas grown in ericaceous potting mix, consider mulching with oak leaf compost or pine needle mulch. Monitor the size of your hydrangea and pot up into a larger container as soon as it begins to outgrow its old one. Potted Hydrangea Care Watering When it comes to caring for hydrangea in pots, the most important thing is watering. It is very important to ensure that the growing medium remains moist (but not waterlogged) throughout the growing season. Feeding You should also replenish the mulch around your pot grown hydrangea each spring. No additional feeding will usually be required. It is important not to provide excessive nitrogen as this can encourage leafy growth and flowering may not be as prolific. One thing to note, however, is that if you are growing a hydrangea that you are trying to keep blue, feeding in summer with low phosphorus, high potassium organic feed can help. You should also water with rainwater where possible. Pruning When and how you prune your hydrangea will depend on which variety you are growing. H. quercifolia will usually only require light pruning in spring – to remove old or damaged stems and old flowers, and perhaps to restrict size a little. H. paniculata should be cut back early in the spring. Pruning is not essential, however, cutting back will restrict growth and keep your plant neater and more compact. This type of hydrangea produces flowers on new wood, so you can prune back quite heavily on last year-s growth. Aim for a healthy framework 30-60cm high. Prune each stem just above a pair of healthy buds. H. macrophylla should be pruned in the middle of spring. They produce their flowers on old growth, so pruning back too hard could mean that you lose the flowers for the year. Leave the dead heads over winter, to protect the new growth, then cut these back carefully to the buds which are forming underneath each one – this is where the new flowers will form. If your plant is overgrown, you can also cut some stems back to the base.
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Microgreens Can Be Grown At Home Year-Round For An Endless Supply - Here's How
IN THIS GUIDE What Are Microgreens? Commonly Grown Microgreens How To Grow Microgreens 1) Fill Your Containers 2) Sow Your Seeds 3) Water Your Seeds 4) Place In A Warm, Sunny Spot 5) Replenish Your Seeds! 6) Harvesting Your Microgreens Common Problems References Microgreens, or micro leaves, as they are sometimes known, are simply salad, herb and vegetable plants harvested much earlier when they are still small. They are simple to grow and incredibly flavoursome. If the idea of growing microgreens at home seems a bit alien, don’t worry – this guide will cover what they are and how to grow and care for them. What Are Microgreens? Microgreens are simply the very young plants of the herbs, salad and vegetables you might normally eat or grow at home, only harvested when they are tiny. Microgreens are really versatile and can be grown on a windowsill, greenhouse or even outside during the warmer months. If grown inside, it is even possible to produce them year-round for an endless supply. It is thought that they were first introduced in an American restaurant as early as the 1980s, but didn’t become more well known until later and the big global business they are today.1 When learning about microgreens, it is important to note that they are not the same as sprouts – which can be grown in a similar way, but the difference being that microgreens have true leaves, and take slightly longer to grow before being ready to eat. Microgreens are widely available to purchase fresh here in the UK – however, they’re also a great option to grow at home and get children involved in growing their own food. The process can be a fun and sensory experience and the fact that they grow so quickly helps keep them interested. Commonly Grown Microgreens Microgreens can encompass a huge variety of plants in an array of colours and tastes, including herbs, salads, brassicas, legumes and grasses. The most common ones grown here in the UK, categorised by families include: Brassicaceae Family Includes: Broccoli, cabbage, rocket, kale, watercress, mizuna, mustard and radish. Leguminosae / Fabaceae Family Includes: Pea, broad bean. Asteraceae Family Includes: Lettuce, endive. Lamiaceae Family Includes: Mint, oregano, basil, lemon balm. Poaceae Family Includes: Wheatgrass. Some microgreens, such as mizuna and rocket can be a bit spicy, even bitter and others like basil almost sweet, so there is something for everyone’s taste buds. How To Grow Microgreens 1) Fill Your Containers Microgreens can be grown in almost anything, from seed trays and yoghurt pots to lengths of guttering. The containers do not even have to have drainage holes, but this can help. To grow microgreens, fill your container, almost to the top, with a fine-grade compost and gently tamp the soil down. You can also use a linen mat as shown in the example above. 2) Sow Your Seeds Unlike when growing ‘normal’ sized plants, microgreen seeds can be sown rather thickly. This is because the shoots are going to be harvested much sooner and the plants are not going to grow large and compete for space. Once the seeds are sown, press them down gently. 3) Water Your Seeds Water with a spray bottle ensuring the seeds and compost are moist. Using a spray bottle, rather than a jug or watering can, is a gentle way of watering and will reduce any likelihood of the seeds being dispersed. It is often recommended to soak the seeds overnight, prior to sowing, to speed up germination, but this is not strictly necessary as they are such a quick-growing crop anyway. 4) Place In A Warm, Sunny Spot For the seeds to germinate, place the container on a sunny windowsill, south facing is ideal and remember to keep the soil moist. In the right environment, the seeds should germinate within 2 – 3 days. Having germinated, the microgreens need light to continue to grow. A sunny windowsill is more than adequate usually, but lights, such as LED grow lights can be used, especially in winter when light levels are at their lowest. Continue to keep the seedlings well-watered, but don’t overdo it, as overwatering can lead to problems, including mould growth. 5) Replenish Your Seeds! If you get the bug of growing microgreens, it can be surprising how quickly you go through seeds! Thankfully seed can be purchased online in bulk bags of 500g or more, which is more cost-effective and should keep you in microgreens for a while. Even old vegetable seeds found in the bottom of the garden seed tin are worth a go and often work well. This is especially true of brassicas – the seeds are so small and there are often many left to be found at the bottom of the packet. It is possible to have a continual supply of microgreens, rather than a large glut, through a process called successional sowing. This isn’t as complicated as it sounds; it simply means sowing a new batch of seeds every week, so that as one batch has been harvested another one is growing on and almost ready. 6) Harvesting Your Microgreens Once the plants are about 5 – 7.5cm tall and usually after 2 – 3 weeks, the shoots are ready for harvesting. The main thing is that they have developed their true leaves. To harvest, simply cut just above the substrate with a clean and sharp pair of scissors or snips and enjoy. Microgreens are best eaten fresh and one of the great things about growing microgreens at home is that you only need to harvest what you need then and there – the rest will happily continue to keep until you next need them. Some microgreens will regrow, especially if cared for and if cut just above the lowest leaf. If they don’t or if you would rather sow a fresh batch, the old soil can be composted and you are ready to start again. Common Problems Why Are My Microgreens Falling Over? Microgreens falling over can be a rather common problem when growing at home and there can be several causes. Lack of water is possibly the most common reason, so try giving them a good drink and see if they recover in a few hours. But do water gently as the pressure from a jug or tap can force them over as well. Another potential cause of them falling over is because they have grown too thin and leggy and subsequently become weak. This is often because they have not received enough light and may need to be moved to a sunnier spot or placed under a grow light. “Stems rotting off where they meet the soil is another common cause of collapsing,” says Colin Skelly, a Master Horticulturist. “This can be caused by overwatering or lack of drainage from the pot. Adding some grit to the sowing mix could help.” Why Haven’t My Seeds Germinated? Seeds might not germinate for a number of reasons, including the seeds being too old, of poor quality or not being in proper contact with the soil. Germination usually only takes a few days, so any longer and it might be worth checking the sow by date of the seed packet or trying a different brand if it continues. It’s important to remember that seeds need good contact with the soil, the right temperature and to be kept moist, as poor germination can often be caused by just poor soil contact, being too cold or being allowed to dry out. Why Is There Mould On My Microgreens? Mould on microgreens can sometimes be confused with white root hairs, which are usually nothing to worry about and often disappear in a few days. If the white substance around the base of the seedlings does not look hair or feather-like, then it is most probably mould. Mould is most often caused by poor drainage, so if you are using trays or containers without holes, it might be worth trying one with holes, to allow excess water to drain. High humidity can also encourage mould, so opening a window or placing the seed tray in a more ventilated space may help. A lack of light can also be the culprit so increasing the available light may help prevent mould. Using a soil or compost which does not have good drainage may also contribute to mould growth. A freer draining compost mix could be tried or even adding some perlite to the compost mix may well help. Lastly, it is really important to practise good hygiene and clean the trays and containers thoroughly after use and allow them to dry before stacking and putting them away until next time. The best course of action against mould is to try and prevent it in the first place, as if your microgreens do unfortunately get mould, then it is recommended not to consume them. References 1. Role of Microgreens and their Potential Health Benefits: A Review. (n.d.). JETIR. Retrieved March 17, 2023, from https://www.jetir.org/papers/JETIR2105366.pdf
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