Growing
Divide Alstroemeria Tubers In 4 Steps To Reduce Overcrowding And Produce New Plants
IN THIS GUIDE Why Divide Alstroemeria? When To Divide Alstroemeria How To Divide Alstroemeria Tubers 1) Lift The Plant From The Soil 2) Prepare the Root Ball 3) Separate The Tubers 4) Replant As Quickly As Possible Planting Considerations Dividing Alstroemeria tubers is an easy garden job. Like other perennials, Alstroemerias can be divided to reduce overcrowding and propagate new plants. Why Divide Alstroemeria? There are two main reasons why you should divide Alstroemerias (and other clump-forming perennial plants). The first reason is to clear space and reduce overcrowding in a bed or border, or to stop a mature plant from outgrowing its container. The second reason is, of course, to propagate your plant, and obtain new plants for your garden. Propagation by division is the easiest way to get new Alstroemeria plants, since these plants are not easy to grow from seed. If you collect your own seeds then the plants you grow may not look the same as their parent. Plants grown from seed will also take several years to flower. When you divide Alstroemeria, you will obtain a number of plants immediately, each of which will be an exact copy of the parent plant. These new plants can also be placed in new containers, or elsewhere in your garden right away. Dividing plants is a great way to make new plants to fill new areas in your garden and to improve existing growing areas. When To Divide Alstroemeria Alstroemerias are best divided in April, though you may also undertake the task in May. While other summer flowering plants can often also be divided in autumn, between September and November, this is not the best time to divide Alstroemeria tubers because they can be a little tender. Also, because the new plants must be planted right away, spring sowing gets them the easiest start. If your Alstroemeria is growing in a bed or border, among other perennial plants, it is best to think about dividing your clumps every 2-3 years or so, even if you are not in need of new plants. This ensures that the plants remain healthy and flowering well, and will also help to prevent overcrowding in the growing area. How To Divide Alstroemeria Tubers A little more care is required when dividing Alstroemeria tubers than is required when dividing many other perennial plants, but it is still a relatively easy job. 1) Lift The Plant From The Soil Alstroemerias have fragile roots and they may not cope well with any damage, so it is very important to be as careful as possible at this stage. Place a garden fork or spade into the soil at some distance from the base of the plant. Then gently lever to raise the plant out slowly, easing it out of the soil (or container as shown in our case). 2) Prepare the Root Ball Now that the root ball is above ground, carefully examine it. Gently knock off excess soil so that you can see the tubers clearly. Again, be very careful not to damage the roots. You will note that the tubers are tangled together into a clump. 3) Separate The Tubers As you examine the root ball, you can now gently begin to disentangle individual tubers from the clump. At this stage, you will have to decide how many new plants you wish to make from this parent plant. Often, you will be able to simply tease the tubers apart by hand. Occasionally, you may wish to use a sharp knife to separate roots that are particularly enmeshed, though this is not usually required. 4) Replant As Quickly As Possible The key thing to remember about Alstroemeria tubers is that, unlike tubers of many other plants, they will not store well. You need to make sure that you replant your divisions as soon as possible, either into containers or a suitable spot in your garden. Colin Skelly advises: “When you are dividing more than one cultivar, make sure that you label your pots straight away.” “Once plants are mixed up there is no way to know which is which until they next flower – by which time it is too late to move them.” Remember, as mentioned above, Alstroemerias require reasonably fertile soil, which is free draining, in a sunny and sheltered spot. If using containers, these should be filled with John Innes No. 2 compost or a homemade equivalent. Planting Considerations Alstroemeria plants should be replanted to the same depth that they were at in the previous location or container. Simply bury the tubers and leave any shoots sticking up above the surface of the soil or growing medium. Divisions of tubers should be planted to a depth of around 15cm. Mulching around the plants with organic matter to add fertility, reduce moisture loss and suppress weeds to a degree can be a good idea. However, make sure that the mulch does not actually touch the base of the plants. The divisions should begin to produce new growth and flowers within 15 weeks. Be patient and do not be tempted to give up on your tubers if you are worried that they are not yet growing. Wait for at least four months before determining that something has gone wrong. Keep the area moist but do not overwater – the tubers can rot in damp soil and prolonged waterlogged conditions. Remember that more watering will be required when growing in containers.
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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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Choosing 15 Clematis Varieties For Shade With The International Clematis Society
IN THIS GUIDE Spring Flowering 1) C. montana var grandiflora 2) C. montana var. rubens ‘Tetrarose’ 3) C. alpina ‘Pamela Jackman’ 4) C. alpina ‘Helsingborg’ 5) C. macropetala ‘Wesselton’ Early Summer Flowering 6) ‘Marie Boisselot’ 7) ‘Niobe’ 8) ‘The President’ 9) ‘General Sikorski’ 10) ‘Nelly Moser’ Summer and Autumn Flowering 11) ‘Jackmanii’ 12) ‘Gipsy Queen’ 13) ‘Perle d’Azur’ 14) ‘Comtesse de Bouchard’ 15) ‘Hagley Hybrid’ Clematis plants can be wonderful for bringing some light and brightness to a shady spot. It is a versatile genus of flowering plants, which offers options for almost any setting. “Clematis flowers are incredible, they give a real display and last a long time,” says Fiona Woolfenden, Secretary of the International Clematis Society. “Clematis are reliable if planted in the right conditions and come up every year and by picking certain varieties, you could have a clematis in flower every month of the year!” The shade-tolerating clematis climbers listed below will be great options for many shady spots, such as up against north-facing or east-facing walls or trellis fencing. “I like to grow Clematis up and through trees and hedges,” explains Master Horticulturist Colin Skelly. “This takes advantage of the support offered by trees and hedges and provides a more naturalistic feel than growing up a trellis or pergola.” Spring Flowering Spring flowering clematis are prized for their beautiful, often delicate blooms which appear early in the season. Many which flower in spring are tolerant of a more shaded spot. Some options to consider are: 1) C. montana var grandiflora HARDINESS RATING: H5 FLOWERING MONTHS: SPRING AWARD OF GARDEN MERIT This is one of my own personal favourites. We have an extremely large and abundant plant of this type growing along a hedgerow at one side of the garden. It flowers prolifically, not just on the sunny south side of the hedge adjacent to the road, but also on the north side of the hedge facing the garden. The pristine white flowers emerge in late spring and early summer. It is a very vigorous climber which can quickly grow to brighten up a shady spot. 2) C. montana var. rubens ‘Tetrarose’ HARDINESS RATING: H5 FLOWERING MONTHS: SPRING AWARD OF GARDEN MERIT Another of the Montana group of clematis, ‘Tetrarose’ has beautiful flowers with mauvish-pink petals and light yellow stamens. With similar characteristics to the above, other than the flower colour, this can be another wonderful early season clematis to consider for a partially shaded spot. 3) C. alpina ‘Pamela Jackman’ HARDINESS RATING: H6 FLOWERING MONTHS: SPRING AWARD OF GARDEN MERIT “Spring-flowering clematis comes mainly from a group known as atragenes, which grow in alpine areas, but not above the snow line,” explains Ken Black, from the plant nursery Ken Black Clematis. C. alpina begins the list of 3 plants from this group that can cope with some shade. The deep purple flowers, around 7cm wide, emerge from mid to late spring, and fluffy seed heads follow. This is a clematis which is even hardier than the two options mentioned above. It will survive across all of the UK, even in extreme winters. 4) C. alpina ‘Helsingborg’ HARDINESS RATING: H6 FLOWERING MONTHS: SPRING AWARD OF GARDEN MERIT This is another in the Atragene Group, and also has nodding bell-shaped flowers. “They are used to cold, windy conditions on the edge of forests or on screed slopes where the soil is well-drained,” says Ken, when discussing the properties of Atragene clematis. “Because of their hardiness, varieties bred from this group are ideal for UK gardens, as long as their native conditions can be somewhat replicated.” This particular cultivar has beautiful deep pinkish-purple flowers around 5cm long. Like the above, these appear in mid to late spring. 5) C. macropetala ‘Wesselton’ HARDINESS RATING: H6 FLOWERING MONTHS: SPRING AWARD OF GARDEN MERIT A third selection from the Atragene Group clematis, ‘Wesselton’ is another early-season option that really stands out from the crowd. This also has nodding, bell-shaped flowers but the flowers on this clematis are unique. The outer petals are a beautiful violet shade, and a number of staminodes within the flower, blueish with white undertones at the base, give it a double appearance. What is more, these stunning flowers can be up to 10cm across. Ken Black notes that varieties from the Atragene group do not need much pruning but they can be cut back to your desired shape or height if required. Early Summer Flowering Late spring or early summer flowering clematis are also valuable flowering climbers for a somewhat shady spot. Ideally, place the roots in shade and allow the plant to climb up so its head is in the sun. Flowering can be disappointing in a very shady spot, but these cultivars tolerate and even look best in partial shade: 6) ‘Marie Boisselot’ HARDINESS RATING: H6 FLOWERING MONTHS: SUMMER / AUTUMN We have to admit a partiality for clematis with pure white flowers, which stand out really well against deep greens in a more shaded location. When it comes to summer flowering clematis for shade, our top pick is ‘Marie Boisselot’. The large, flat single flowers are a lovely pure white, with light yellow stamens. These blooms can be up to around 20cm in width. With a first and often second flowering, this clematis can be in flower from early summer right through to late summer or even early autumn. 7) ‘Niobe’ HARDINESS RATING: H6 FLOWERING MONTHS: SUMMER AWARD OF GARDEN MERIT This is another early large-flowered clematis to consider for a shady spot. The large, star-shaped flowers of this cultivar are an unusual deep pinkish-red, with a hue that deepens as they age, and contrasts with their greenish-yellow stamens. They can be around 15cm across. 8) ‘The President’ HARDINESS RATING: H6 FLOWERING MONTHS: SUMMER / EARLY AUTUMN AWARD OF GARDEN MERIT This cultivar also has large (up to 18cm in width) and dramatic flowers. In this case, the flowers have eight overlapping sepals with a violet almost shading to silver, and pink and red stamens. This cultivar like the above will flower in early summer, and often again in late summer or early autumn. 9) ‘General Sikorski’ HARDINESS RATING: H4 FLOWERING MONTHS: SUMMER Another beautiful large-flowered clematis that can cope with shade, this cultivar also has large flowers up to 20cm or so across. This option stands out for its brilliant deep purple petals which have a tinge of red at the base. These deep petals contrast dramatically with vibrant and prominent yellow anthers. It is H4 hardy. 10) ‘Nelly Moser’ HARDINESS RATING: H6 FLOWERING MONTHS: SUMMER AWARD OF GARDEN MERIT Perhaps one of the best-known clematis for a shady spot, ‘Nelly Moser’ is famed for its stunning 20cm wide flowers, which have eight distinctive petals, with pale pinkish mauve around the sides and darker pink stripes down the centre of each one. In fact, since the flower colour fades in strong sun, it can be best to grow this clematis in a more shaded position. Summer and Autumn Flowering Summer and autumn flowering clematis are fantastic for adding late-season colour in your garden. Here are just a few of the varieties from this varied group of climbers that will perform well in light or partial shade: 11) ‘Jackmanii’ HARDINESS RATING: H6 FLOWERING MONTHS: SUMMER AWARD OF GARDEN MERIT Jackman’s clematis has been enchanting gardeners since it was developed, as one of the earliest clematis hybrids, in the 19th Century. This is a vigorous, medium-sized climber that will lose its leaves in the winter months, but look great all through summer. The flowers are around 10cm across, in a beautiful shade of violet-purple and a velvety appearance. When it comes to late-season clematis, this is one of our favourites that can cope with a moderately shady spot. 12) ‘Gipsy Queen’ HARDINESS RATING: H6 FLOWERING MONTHS: SUMMER AWARD OF GARDEN MERIT If you love purple flowers, then this cultivar is another great later season clematis to consider. The flowers are 12-14cm across, with velvety purple petals and reddish-brown stamens. This clematis flowers from midsummer to early autumn. 13) ‘Perle d’Azur’ HARDINESS RATING: H6 FLOWERING MONTHS: SUMMER / AUTUMN AWARD OF GARDEN MERIT This cultivar also has purplish flowers, around 10-12cm across, though these are of a lighter, more blueish-violet hue, with purple petal bases blushing a hint of pink on bars down the heart of each one, and yellowish stamens. It is known to bloom prolifically. 14) ‘Comtesse de Bouchard’ HARDINESS RATING: H6 FLOWERING MONTHS: SUMMER AWARD OF GARDEN MERIT This late large-flowered clematis has charming rosy pink, somewhat striped flowers, with creamish-yellow stamens. It flowers from early to late summer and is another cultivar whose colour can fade in a sunnier spot and so which can look best in a little shade. 15) ‘Hagley Hybrid’ HARDINESS RATING: H6 FLOWERING MONTHS: SUMMER / AUTUMN The pretty pink flowers and pinkish-red anthers of this cultivar are also born in abundance on this late-season clematis. They open between midsummer and early autumn to bring an enchanting touch of delicate beauty to a shady spot. These are not the only plants to consider, but they are amongst the best choices for a shady spot. Remember, clematis will rarely flower well in seriously deep shade. But for a somewhat shaded location, the above options are all good ones to consider.
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Restrict Their Spread And Grow Bamboo In Pots To Manage Any Invasiveness
IN THIS GUIDE Bamboo Types For Pots Best Bamboo To Grow In Pots Where To Place Container Bamboo Choosing Containers Filling Containers Planting Bamboo Potted Bamboo Care Growing bamboo in pots can be a great option for small space gardens. There are a wide variety of bamboos that will grow very well in UK gardens. Sometimes, in fact, bamboos can grow so well that they can become invasive. Growing bamboo in pots can help restrict its spread, and also allow you to create a beautiful garden even if you don’t have any space to grow in the ground. Not only will you find it easy to find bamboos that will grow well in containers, you will also find this a very useful crop to grow: Bamboo can be a fairly low-maintenance option, which will not require a lot of your care and attention. Bamboos can work very well for screening and privacy, and can also provide you with a range of yields. Many bamboos provide edible shoots, and you can also harvest more mature bamboo canes for garden use – they can be used as plant supports and in a range of other ways. Bamboo Types For Pots If you have decided that you would like to grow bamboo in containers, then the first step is deciding which type of bamboo to grow. Bamboos are usually divided or categorised as running bamboos or clump-forming bamboos: Running bamboos spread through long underground rhizomes and can increase in spread very quickly. Clumping bamboos grow in dense clumps. These can also still spread rapidly in favourable conditions, but are generally the best choice for growing in containers. Clumping bamboos include Bambusa, Chusquea, Fargesia, Shibataea and Thamnocalamus. However, these are not the only bamboos that can work well in pots. A range of running bamboos can also work well in containers if properly managed. Within both of these types, bamboos can still be extremely varied, both in their vigour and in the eventual size to which they will grow. Some bamboos can easily grow to 5m or more in height, while dwarf varieties (also generally better for growing in pots) can be as small as 30cm or less in height. It is therefore important to consider how large your plant will grow. Best Bamboo To Grow In Pots Fargesia nitida While there are plenty of bamboo varieties that can be grown in pots, some that we recommend are: Chimonobambusa marmorea Fargesia angustissima F. nitida F. rufa Phyllostachys aureosulcata f. spectabilis P. humilis P. nigra Pleioblastus viridistriatus Pseudosasa japonica Thamnocalamus tessellatus Phyllostachys aureosulcata f. spectabilis Where To Place Container Bamboo Most bamboos will thrive in a sunny and sheltered location, however, it is worth noting that there are also bamboos that can cope with some shade, and which can be positioned in a less sunny spot. Bamboos can work well when positioned in individual large containers in a mixed container garden, and can work well within a Japanese inspired garden, or a tropical style garden scheme, for example. Bamboos with edible shoots might not be out of place in an edible container garden, or perhaps in a pot to the edge of a kitchen garden area. Bamboos in containers can also work well to define the edge of a garden area or ‘garden room’. A row of containers with bamboo plants in them can work well to create screening between different parts of your space. They can also be used to increase privacy on the edge of a seating area, perhaps, or along the edge of your property, or to screen unsightly elements within your space. There are plenty of ways to position bamboo in pots to create beautiful and useful effects in your garden. There are also a number of bamboo varieties that can even be grown indoors, as houseplants, so this is another option to consider. Some varieties which can be grown indoors are: Phyllostachys aurea Bambusa ventricosa Chimonobambusa marmorea Pleioblastus pygmaeus P. fortunei When you think about growing bamboo indoors, you might think of ‘lucky bamboo’ but this is technically not actually bamboo at all… Plant Them Up In Spring Ideally, it is best to plant bamboo in containers in the spring. Though you will be able to source and buy bamboo plants in pots throughout the year and can plant them up into their new containers at any time. Just try to avoid planting up on a particularly hot and dry day, or when conditions are particularly poor, as this will increase the transplantation stress on your new plants. Choosing Containers Typically, a container for a bamboo plant will need to be at least 50cm deep and 50cm wide, though a larger planter can also be considered and will mean that you need to repot your bamboo less frequently. The container or containers that you choose should allow for sufficient drainage, yet still enable you to keep the medium within sufficiently moist to suit the bamboo plants you are growing. Make sure there are sufficient drainage holes at the base of the container and consider raising the container on feet or a stand of some kind to make sure there are no waterlogging issues. Kerri Dall from Scottish Bamboo advises: “a raised bed style planter is ideal for bamboo, as the roots don’t grow very deep, but they will stay contained in a raised bed or planter”. With this in mind, especially with running bamboos, a sturdy container is essential. A sturdy wooden planter, for example, can withstand the roots in a way in which other containers cannot. Avoid plastic containers, and remember that for bamboos, glazed pots are generally better than terracotta. Filling Containers Bamboos require loamy soil that is slightly acidic or neutral in pH. Make sure that you choose a reasonably fertile potting mix that is moist, yet reasonably free-draining. To improve the drainage of the container, it can be a good idea to add a layer of horticultural sand to the base of the pot. Planting Bamboo When planting your bamboo plants into new containers or pots, make sure you position it so that it sits slightly lower than it was in its original pot. Place your plant, add your growing medium around the sides and a little on top of the previous surface, firming it gently in place. Water well, then mulch the surface of the container with a good quality compost to help with water retention. Potted Bamboo Care “I really like the versatility of bamboo grown in pots, as they can really add something to a variety of garden situations and styles,” says Master Horticulturist Colin Skelly. “They can provide height, volume, movement and screening and lend an exotic feel to the garden.” “They are low but not no maintenance, so be sure to water, feed, cut back and divide your bamboo when needed and it can be a resilient feature in your garden.” Watering Bamboo plants in pots will require more watering than those grown in the ground. However, they will not require a lot of time or care. Just check the growing medium with a finger twice a week during dry weather, and if the soil is dry a few centimetres below the surface then give your plant a good drink. Remember, bamboos generally dislike very waterlogged conditions. But they do need plenty of moisture throughout the growing season. Feeding Bamboos in containers should be fed each spring with a nitrogen-rich organic liquid feed (such as a nettle liquid feed, or manure tea, for example). A general liquid feed such as compost tea should be applied regularly throughout the rest of the growing season, and the organic mulch should be replenished each year. Pruning In the first year after planting, no pruning is required. However, in subsequent years, it is a good idea to remove any canes which are dead, damaged or weak, cutting them to the surface of the growing medium. If the clump has become congested, cut out some additional canes to let in more light and air to the centre of the plant. Potting On / Repotting Every few years, bamboo plants will need to be potted on into a larger container, or divided and repotted into several new pots. If you are dividing bamboo, this is best undertaken in the spring. Use younger rhizomes from around the edges of the clump to establish new plants.
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Experts Reveal How To Force Rhubarb For An Early Crop (Make It Grow Faster And Earlier)
IN THIS GUIDE What Is Forcing? How To Force Rhubarb 1) Prepare The Area 2) Add Some Compost 3) Cover Your Rhubarb Plants What Else Do You Need To Know? Depending on the circles you move in, rhubarb can be a criminally unsung crop. This vivacious vegetable (yes, it’s a vegetable!) grows big and proud, its characteristic pink-red stalks erupting out of the ground and into the sky. When picked and trimmed of its leaves, the stalks are delicious and versatile. Never a dull moment with rhubarb One thing that makes rhubarb a popular crop for those of us in the know, is how easy it is to grow. Rhubarb needs little care or attention, evidenced by how often you’ll find it in the wild if you know where to look. It grows well in warm and dark conditions, and has a long harvesting season that can start in winter if you know how – great for incorporating into your growing calendar to ensure you’ve got something ready to harvest for as much of the year as possible. In this article we’ll teach you how to force rhubarb: a technique that brings the start of the harvesting season forward slightly. This should be of interest whether you’re a long-time fan or a complete amateur. What Is Forcing? Put simply, forcing is a way to make rhubarb grow faster and earlier in the year than usual. Forcing is basically tricking the plant into thinking it’s spring, encouraging it to grow more quickly towards what it thinks is the warm springtime sun. This is achieved by simulating warmer growing conditions during winter, and it’s surprisingly easy to do. How To Force Rhubarb There are only a few steps to forcing rhubarb, none of which are difficult. 1) Prepare The Area First up you’ll want to clear the area at the base of a fledgling rhubarb plant. This means removing weeds, old leaves, and any garden detritus that may have gathered around. 2) Add Some Compost Next you need to spread a little compost around the rhubarb, taking care that it doesn’t actually touch the stalks. Doing so can burn the crop and hinder its ability to grow. Just put it in a ring a couple of centimetres away from the plant. 3) Cover Your Rhubarb Plants This is the crucial step: you’re going to cover your rhubarb with a pot, trug, bucket, or similar container. Choose something opaque to block out all-natural light, and ideally with only one hole to allow airflow. Terracotta pots make for great forcing If your covering is made of a light material that may get blown away in strong winds, make sure to weigh it down with a brick or something similar. Plastic plant pots and buckets will definitely require weighing down to prevent them from being blown around your garden once the wind picks up. How Long Does Forcing Take? It takes anywhere over three weeks to force rhubarb. When you check under the containers you’ll see thick pink stems, and these are ready to pick when they’re upwards of about 18cm. The longer you leave your rhubarb the bigger it will get, although check in occasionally to make sure things aren’t getting too cramped. Depending on how many rhubarb plants you have and the weight of the container, you may even see the stalks lifting the container off of the ground! As we said earlier: rhubarb is very enthusiastic. Remove The Leaves Before you do anything with your rhubarb, remove and dispose of the green leaves. What Else Do You Need To Know? Now we’ve introduced the technique for forcing rhubarb (we told you it was easy!), here are a few things that should help you to see better results. Number one: where possible, only force established rhubarb plants as the process is quite intensive, and younger plants can take longer to recover. Once you’ve forced a rhubarb plant and harvested the resulting crop, don’t harvest again from the same plant for the rest of that year, even if it grows decent-looking stalks. You need to give the plant time to rest to put it in best stead for a strong and healthy harvest in subsequent years. Follow these steps to keep your rhubarb crop in good condition Don’t worry about running out of rhubarb early if you force your crop though: it’s easy to stagger things to give yourself multiple harvests. To do this, just leave some plants uncovered to grow at their natural pace. Your forced crop will be ready within a few weeks of being covered, and you can harvest the remainder as and when it starts to look ready. For a plant with a long harvest season, sometimes up until late August, this gives you a lot of flexibility. You can also split rhubarb to give yourself a greater number of plants to grow. Once you start experimenting with rhubarb – both in terms of growing techniques and recipes for your harvest – we’re sure you’ll grow to love it.
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8 Autumn-Flowering Perennials For Late Interest Recommended By Garden Designers
IN THIS GUIDE 1) Japanese Anemone 2) Aster 3) Sedum 4) Salvia 5) Nerine 6) Echinacea 7) Rudbeckia 8) Agastache Autumn can sometimes be thought of as the end of the summer colour in the garden and the arrival of autumnal foliage. But it needn’t be, as there are some wonderful perennial plants that continue blooming or begin to burst into flower at the end of the summer, providing some stunning late-season interest. “Autumn is my favourite time of year to be in the garden, because it is beautiful and also never too hot or wet,” shares Paul Hervey-Brookes, an award-winning Garden Designer. What’s more, being perennial and presuming the winter is not too harsh, these plants will keep coming back year on year, providing great value for money. Perennials are also relatively maintenance-free, often requiring only deadheading and cutting back at the end of the year. 1) Japanese Anemone Anemone x hybrida ‘Honorine Jobert’ HARDINESS RATING: H7 TYPICAL FLOWERING MONTHS: AUGUST – OCTOBER RECOMMENDED VARIETY: Anemone x hybrida ‘Honorine Jobert’ From the Ranunculaceae family, these flowers are herbaceous perennials, most originating, not from Japan, but from China. Japanese anemones really come into their own in autumn. They begin to flower in late August and will continue until October or the arrival of the first frosts. They are happiest in either full sun or part shade and prefer a moist, well-drained soil. They are hardy, but may however struggle in wet winters. Flowering in either pinks or whites on tall stems rising above the foliage, they are great for the back of the border. After flowering, cut back the stems and remove any dead foliage in early spring. Beware though, Japanese anemones don’t like being moved once established and have a tendency to spread, almost to the point of being invasive. If there is space for only one, Anemone × hybrida ‘Honorine Jobert’ is a stunning plant. Growing to H1.5m x W1m, in almost any soil, it produces pure white single flowers for months on end. 2) Aster Aster × frikartii ‘Mönch’ HARDINESS RATING: H7 TYPICAL FLOWERING MONTHS: JULY – OCTOBER RECOMMENDED VARIETY: Aster × frikartii ‘Mönch’ Better known as the Michaelmas daisy, although recently classed botanically as Symphyotrichum, perennial asters are often described as a stalwart of late summer and early autumn colour. Available in blue, purple, pink and white, there is one for every garden. A favourite of pollinators, they will attract wildlife into the garden and flower for months on end from July until the first frosts. Ideal for a cottage garden scheme, asters grow well in any well-drained soil apart from clay. Preferring full sun, they can cope with a sheltered or exposed site. They can be cut back after flowering or the seed heads left on for winter interest and the birds to forage amongst during the colder months. For stunning purple-blue flowers with a yellow centre, blooming from July until October, try Aster × frikartii ‘Mönch’. With good resistance to mildew and growing to 1m in height and 0.5m wide, it is perfect for a mixed border or a container but may need staking earlier on in the year. 3) Sedum Sedum spectabile HARDINESS RATING: H7 TYPICAL FLOWERING MONTHS: AUGUST – OCTOBER RECOMMENDED VARIETY: Sedum ‘Autumn Joy’ Sedum, or as they are now known as ‘Hylotelephium’, are a group of hardy and sun-loving perennials. With star-shaped flowers set in clusters, they flower from summer into autumn. A drought-tolerant plant, they prefer full sun and grow best in a south-facing spot and well-drained soil. As a valuable source of nectar later in the year, they are loved by pollinators and require little maintenance, as their faded stems can be left for winter interest and cut back in early spring. Hylotelephium ‘Herbstfreude’ or as it was better known – Sedum ‘Autumn Joy’ – is a great variety producing vibrant pink flower heads which darken to red over time and brown over winter. With an eventual size of 0.6m tall and 0.4m wide, it looks great planted alongside ornamental grasses. 4) Salvia Salvia amistad HARDINESS RATING: H3 TYPICAL FLOWERING MONTHS: MAY – SEPTEMBER RECOMMENDED VARIETY: Salvia ‘Amistad’ Salvias, or ‘sages’, are a wide group of plants including microphylla, nemrosa and sylvestris cultivars. “I think the best thing you could possibly do is to take a loam-based compost, add it to your container and place a Salvia microphylla into the pot,” shares Garden Designer Lachlan Rae. “Having said that, there are so many varieties to use that are all relatively hardy.” Whether as annual bedding or perennial plants, they are a must-have for any border or container. With so many to choose from, the perennial Salvia ‘Amistad’ has to be a firm favourite though. Producing the most stunning deep purple flowers and black calyces, it really stands out. Growing in an upright habit to H1.2m x W0.5m, it is well suited to the back of the borders and will flower, if deadheaded regularly, from May through to the end of September. A drought-tolerant plant, it requires a sunny and sheltered spot – a south-facing border is ideal. Even though hardy it may not survive the worst winters, but thankfully it takes easily from cuttings to provide backups. 5) Nerine Nerine bowdenii HARDINESS RATING: H5 TYPICAL FLOWERING MONTHS: AUGUST – OCTOBER RECOMMENDED VARIETY: Nerine bowdenii ‘Isabel’ Nerine bowdenii, or the ‘Bowden lily’ is a hardy, bulbous perennial and part of the Amaryllidaceae family. Originating from South Africa it is no surprise that it favours a well-drained soil and south-facing aspect. So much so that it will not flower if planted in shade. The flowers protrude above its bright green foliage and will brighten up the autumn months from September until November. Growing to around H.5m they are well placed for the front of the border or a container. Nerine bowdenii thrive in poor soil – if the soil is too rich it will encourage more foliage rather than blooms. They hate to be moved so only do so if necessary and don’t despair if they don’t flower afterwards, as they will more than likely bloom the following year. For a spectacular pink flower 8cm across, Nerine bowdenii ‘Isabel’ is worth considering. Growing to 0.5m tall and 0.1m wide, it will benefit from a mulch after flowering to help protect over winter. Over time the bulbs will make offsets and form a clump, even becoming crowded, but don’t worry as they will often flower better when allowed to bulk up. If blooms decrease and the clump gets really large, then they can be divided up and replanted in spring. 6) Echinacea Echinacea purpurea HARDINESS RATING: H5 TYPICAL FLOWERING MONTHS: JULY – SEPTEMBER RECOMMENDED VARIETY: Echinacea purpurea Echinacea or ‘coneflowers’ as they are commonly known, originate from North America and must be one of the best plants for late summer and autumn colour. Being a rhizomatous perennial, they die back over winter and new growth appears in spring. Preferring full sun, they will tolerate some shade and are most at home in a south-facing spot. Displaying daisy-like flowers in a range of colours including, orange, red, pink and white, they are certain to add an injection of colour later in the year. Now very popular due to prairie style planting, they look equally good in a cottage garden and are loved by pollinators. “To provide a long season of nectar for pollinators, using late summer or early autumn flowering perennials is a must,” explains Master Horticulturist Colin Skelly. “There aren’t many native UK later flowering plants, so using plants like Echinacea and the others in this list, can really help to give a boost to the resources available to pollinators in the UK.” Echinacea purpurea or the purple coneflower is a striking example, producing huge 12cm diameter purple flowers in summer until right into the autumn. Reaching H1.5m x W0.5m they look great at the back of the border and do best in well-drained soil. 7) Rudbeckia Rudbeckia fulgida HARDINESS RATING: H6 TYPICAL FLOWERING MONTHS: AUGUST – OCTOBER RECOMMENDED VARIETY: Rudbeckia fulgida var. sullivantii ‘Goldsturm’ For a dazzling yellow late summer display of colour, Rudbeckia or black-eyed Susan as they are also known, can’t be beaten. From July, Rudbeckia produces bright yellow flowers with a brown central disk. A stunning plant, it is perfect for planting in drifts amongst other perennials or ornamental grasses. Originally from North America, they can be annual, biannual or perennial and are particularly easy to grow. Preferring a moist and fertile well-drained soil, they will thrive in a south-facing spot and are lovely as a cut flower due to their long stems and vase life. Most varieties here in the UK are perennials, apart from Rudbeckia hirta, which is not reliably hardy here in the UK and tends to be grown as an annual. Out of the herbaceous perennial varieties, Rudbeckia fulgida var. sullivantii ‘Goldsturm’ is one of the best known and for good reason. It produces an abundance of large flowers on tall stems until the first frosts and is reliably hardy. Listed by the RHS as a plant for pollinators, it will bring bees and other pollinators into your garden when in flower. 8) Agastache Agastache ‘Blue Fortune’ HARDINESS RATING: H6 TYPICAL FLOWERING MONTHS: JULY – SEPTEMBER RECOMMENDED VARIETY: Agastache ‘Blue Fortune’ Agastache or giant hyssop is a perennial plant that blooms on spires from July until October. Usually with purple or mauve flowers, other colours now include orange and pink. A tough plant, it is drought tolerant and can put up with poor soil. It requires full sun, ideally in a south or west-facing situation. It can add great height and structure to the garden, but is a short-lived plant and may need replacing every few years. Agastache ‘Blue Fortune’ is a wonderful plant sending up spikes of violet-blue flowers for months on end. Growing to H1m x W0.5m it looks equally good in a border or container. The flowers are a favourite of bees and can be left once faded to add some interest over the winter months. Autumn doesn’t have to mean the demise of colour in the garden, so why not try some of these late-flowering perennials to extend the flowering season.
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