Growing
Learn Why Pruning Astilbe In December Or January Is The Best Policy
IN THIS GUIDE When To Prune 1) Prune Stems & Foliage To The Base 2) Use Or Compost The Dead Stems Astilbe is a reliable and low-maintenance perennial that will thrive in a partially shaded and moist spot in your garden. Gardeners will find that this plant requires very little care and that it is a great addition to a wildlife-friendly garden. One simple and easy annual job when growing Astilbes is pruning your plants. To prune Astilbe: Cut back faded stems after flowering, or wait until December or January. I typically recommend that you opt for the latter option. Cut off inflorescences (flowering stems) and foliage right to the base. Use the dead stems in flower arrangements indoors, or add all the materials to your compost heap. Read on for a more in-depth explanation of this process. Difficulty Easy Equipment Required Secateurs When To Prune December – January When To Prune Deadheading Astilbes is not required and is not usually desirable. There are really only two reasons why you may choose to do so, and many more reasons to leave the plants to go to seed and leave the dead flowering stems in place. You may choose to remove the flowering stems as soon as the flowering is done: For aesthetic reasons To prevent the plants from self-seeding Most people actually like the look of the brown spent flowering plumes, which can add depth and interest, and architectural form to the autumn and winter garden. However, you may choose to remove these at the end of the flowering season if they do not fit in with your garden scheme or you do not personally find them appealing. Occasionally, Astilbes may self-seed if they are happy where they are grown. However, this is not all that common and even when these plants do self-seed, they are not going to take over. So, self-seeding is usually viewed as beneficial where it does occur. However, if for some reason you do wish to prevent this, you can prune back your Astilbes as soon as the flowering is done. That said, there are plenty more reasons not to deadhead, and to leave the Astilbe unpruned until December or January. Pruning in December or January is the best policy because: Most people agree that the dead inflorescences still look good – adding structure and interest to an autumn and early winter garden. Leaving the flower heads to go to seed offers the chance of self-seeding, where this may be viewed as beneficial. It will take a few years for seeds to grow into flowering plants, but this could be a free way to get new plants for your garden. The seed heads and the foliage also provide food and habitat for a range of wildlife in your garden, so leaving pruning until a little later is the best choice in a wildlife-friendly garden. Pruning before spring arrives is a good idea because it reduces the chances of pest or disease problems relating to rotting foliage and overcrowding, and makes way for new growth which will emerge in the early spring. 1) Prune Stems & Foliage To The Base The pruning itself really could not be any simpler. All you have to do is take a clean and sharp pair of secateurs or gardening shears and cut off all the vegetation of the plant right down to ground level. 2) Use Or Compost The Dead Stems It is best not to leave the plant material that you have cut lying around, since Astilbes can sometimes be more prone to pests or diseases, such as powdery mildew, if you leave the debris in place. Instead, consider whether you would like to use the dead stems in floral arrangements inside your home. These can look rather attractive with dried flower arrangements over the winter months. If you do not wish to make use of the plant material in this way, remember that you should return the nutrients it contains to your garden. Add all the pruned material from your Astilbes to your compost heap with other organic materials, where it will rot down and make a valuable compost which can be added as a mulch around Astilbes and all your other perennial plants in the spring.
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Established Astilbe Should Easily Survive Winter, But You May Wish To Cut Back And Mulch
IN THIS GUIDE 1) Deadhead In Summer Or Autumn 2) Cut Back In Winter 3) Mulching Astilbes are great for a moist, partially shaded spot in your garden, and when grown in conditions which they enjoy, they can flower reliably over a number of years. These are fully hardy herbaceous plants, which will die back each winter, before bursting into a new life in the spring. Astilbes are also excellent low-maintenance perennials, which will not require a lot of care or attention – especially once established. In the UK, Astilbe will sail through the winter with ease before coming back into active growth in spring. But before winter arrives, there are a couple of options that you might consider when it comes to caring for your Astilbes: Cut back the dead flower heads in summer/autumn to keep things neat over winter. Wait until December or January before cutting back hard before new growth emerges. Mulch around the plants in the autumn with organic matter. Some gardeners will choose to care for Astilbes by cutting back the brown, dead flowering heads before winter, but, as discussed below, we recommend that you wait until later before cutting back. 1) Deadhead In Summer Or Autumn The main reason that gardeners might choose to remove spent flowering plumes or inflorescences early is to prevent the plant from self-seeding. In areas where optimal conditions are available, these plants can occasionally self-seed. This can be interesting, though plants may not resemble their parent plant. If you wish to prevent the plants from going to seed, then you can cut off the spent flowers before the seeds form. However, self-seeding is rarely prolific, where it occurs at all, so these plants are not in any way likely to take over your garden. Therefore, deadheading is not required for these plants. Gardeners may also simply choose to deadhead at the end of the year to keep things looking neat and tidy in the winter garden. This is to some extent a matter of personal preference, but there are several reasons to consider holding off before you cut back Astilbe plants. 2) Cut Back In Winter If you leave Astilbes alone once the flowering has finished, one benefit is that over autumn and early winter, the deadheads can actually look rather attractive. They can still have an impressive upright form and, though they have faded to brown, can add architectural drama to a perennial border or another suitable spot in your garden. As autumn wears on and winter begins, these dead stalks and the foliage also, crucially, provide valuable habitat and food sources for winter wildlife. So, if you want to have a wildlife-friendly garden, you should leave these in place before you cut all the stems and foliage off in late winter to make way for new growth in the spring. 3) Mulching “Astilbes prefer rich, moist soils, so a mulch of organic matter around the plant in the late autumn after rain will conserve moisture in the soil and improve its structure,” shares Master Horticulturist Roy Nicol. “Allowing your astilbe plants to access nutrients in the soil will help to support strong growth in the spring.”
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Astilbe Can Be Sown From Seed But It's Not A Reliable Method - Here's Why
IN THIS GUIDE Why It’s An Unreliable Method Astilbe Is Best Sown Indoors 1) Collect Seeds 2) Store Seeds Until Spring 3) Soak Seeds Before Sowing 4) Sow The Seeds 5) Pot On Then Plant Out Astilbes are beautiful flowering perennials, perfect for a moist, partially shaded spot. If you already have a mature plant in your garden, you might be wondering how best to propagate it to gain more plants. While dividing Astilbes or growing from bare roots are far easier and more reliable propagation methods, you can also grow Astilbes from seed. Why It’s An Unreliable Method Gardeners tend to choose other methods of propagation because: Varietals will often not come true from seed, so, while the results can be interesting, the plants may not be very similar to the parent plant. Germination rates can be low, so seed sowing is not a very reliable way to ensure new plants. Plants sown as seeds will take several years before they flower. Astilbe varietals grown from collected seed also tend to be rather short-lived. Occasionally, Astilbes which are very happy in their spot in your garden may self-seed. If they do so, you can replant these volunteer seedlings into their growing positions in either September or in around April, or you can leave them where they have naturally chosen to grow. If you do decide that you would like to collect seeds to sow: Collect seeds from your existing Astilbe plant. Store seeds until spring. Soak the seeds in water for 24 hours. Sow the seeds in moist seed-starting compost in flats, trays or small pots indoors in early spring. Plant seedlings out into their final growing positions in September or October. Read on for a more detailed explanation of each of these steps. Difficulty Medium Equipment Required Seeds, seed starting pots or trays, potting mix When To Sow March-April When To Plant Out September-October Astilbe Is Best Sown Indoors Astilbe seeds are best sown indoors in early spring and then planted out into your garden in September or October. 1) Collect Seeds The first step is to collect the small seeds from your Astilbe. After the flowers have bloomed, the seeds will form along the feathery flowering heads, which are technically called inflorescences. If you do not deadhead, you can collect the stems before the seeds scatter. Lay out the stems to dry somewhere dry and once the pods seem ready to split open, place them into a paper bag. Give the bag a good shake and let the seeds fall into the paper bag. Then, collect the seeds and place them into a paper envelope or another suitable container to keep them safe and dry until spring. 2) Store Seeds Until Spring It is best to store the seeds until spring before planting because older seeds which have been stored carefully over the winter stand a somewhat better chance of germinating successfully. Keep the seeds in your fridge or in another cool location. 3) Soak Seeds Before Sowing In early spring, take your seeds out of storage and place them in tepid water to soak for 24 hours. This is another strategy which can improve germination rates. 4) Sow The Seeds Prepare a suitable seed-starting flat, tray or small pot, filled with a peat-free potting mix which is light and aerated, yet suitable moisture retentive. Scatter the seeds into your chosen seed starting container or containers. “After this step, lightly press them into the compost but do not cover them as they need light to germinate,” shares Master Horticulturist Roy Nicol. “If the seeds are viable and the compost is maintained at around 15°C and kept moist, germination should occur within around 20-25 days.” 5) Pot On Then Plant Out As soon as your seedlings are large enough to handle, prick out the seedlings and pot on into 9cm pots to grow on. Transplant them into their final growing positions in your garden in September or October. Astilbes need a sunny or ideally partially shaded position, with soil which remains moist but does not become waterlogged. Keep the plants well watered throughout the summer months, mulch each spring with plenty of organic matter, and in 3 years or so, there is a chance that your Astilbe grown from seed will reach a size where they will begin to flower.
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Growing Astilbe In Pots? Stick To Smaller Types Says This Horticulturist
IN THIS GUIDE Can Astilbe Be Grown In Pots? Choosing A Container Choosing Potting Medium Potting Up Astilbe Container Growing Care Astilbes are vibrant, hardy perennials which love moist conditions and can thrive in sun or partial shade. They can be a great choice for many different gardens, but if you only have space for containers, then you may be wondering how to grow Astilbe in pots. Can Astilbe Be Grown In Pots? The good news is that Astilbes can certainly be suited to container growing, though when choosing which cultivar to grow, it is important to look for smaller varieties. Some Astilbes will grow rather tall to 120cm in height and can have a spread of up to 1m or more, but there is a range of smaller Astilbe which are more suited to container growing. Most dwarf Astilbes are hybrid types, often with A. simplicifolia as one of their parents, sometimes a descendent of A. chinensis. Dwarf types will be under 60cm in height, with a similar spread. Some cultivars well suited to container growing include: ‘Bonn’ ‘Bronce Elegans’ ‘Europa’ ‘Hennie Graafland’ ‘Maggie Daley’ ‘Mainz’ ‘Rheinland’ ‘Serenade’ ‘Sprite’ ‘Willie Buchanan’ Choosing A Container One of the key things to think about, of course, when you wish to grow Astilbes in pots is which sort of container you should choose, and what size it ought to be. When choosing the type of container, and thinking about what it is made from, remember that Astilbe needs moist conditions, so try to choose a container which does not lose water too quickly. “Terracotta pots are porous and loose moisture relatively quickly, so other materials such as recycled plastic, ceramic or fibreglass should be considered,” says Roy Nicol, Master Horticulturist and Professional Gardener. “Fibreclay made from resin, mesh and clay is another good option, as it is sustainable (using waste outputs from other industries), light and strong.” While they like moist conditions, they do not like excessive waterlogging, so make sure the container you choose has suitable drainage holes at the base. Typically, single Astilbes are grown in pots around 40cm in diameter, with a depth of at least 30cm. Choosing Potting Medium Since Astilbe like moist conditions, and a rich environment, make sure that you fill your container with peat-free multi-purpose compost, or a homemade equivalent, and add some homemade compost or other organic matter for an extra nutrient boost. Mulch around the plant in the top of the container with more compost, or another organic mulch. This will help to retain moisture and also provide slow-release nutrients over time. Potting Up Astilbe Astilbe typically need to be potted up into newly filled containers every 3-4 years. Choose a slightly larger container each time or, when this is no longer practicable, consider dividing your mature plant and repotting each division in its own individual pot. How Many Can You Plant Per Pot? If you have a larger container, you can plant more than one Astilbe in it. When deciding how many Astilbes you can plant per pot, it may be helpful to keep this spacing guide in mind as a rough rule of thumb: Seedlings can be sown and thinned to their eventual spacing when they are around 5-7.5cm tall. Small Astilbes can be planted around 15-20cm apart. Larger Astilbes can be planted around 20-30cm apart. Remember, Astilbe can also be planted in larger containers with other plants which like similar growing conditions. For example, you might plant Astilbe with Primulas, Hostas and Heucheras. Just take care to avoid overcrowding. Choosing larger containers can be a good idea when growing Astilbe and other shade-tolerant, moisture-loving plants. Remember, the larger the container, the more moisture it will retain and the less frequently you are likely to need to water. Container Growing Care Place the pots in a partially shaded spot. However, you should not place your container in deep shade, or the plants will not flower at their best. The most important thing when growing Astilbe in containers is to make sure that the plants are well watered, and that the growing medium stays moist at all times. You should check container-grown plants daily to make sure they do not dry out. Use rainwater whenever possible, and try to water deeply rather than little and often. There is no need to feed Astilbe, just make sure that you grow them in a suitably nutrient-rich potting mix and replenish the organic mulch around the plants each year in spring to provide these plants with the nutrients they need. Leave faded flowers in place for an attractive autumn and winter display. Then, cut back all old growth down to the ground level in the winter before new growth appears in early spring.
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Roy Nicol Shares 10 Award-Winning Astilbe Varieties For Height And Colour
IN THIS GUIDE 1) A. ‘Montgomery’ 2) A. ‘Bressingham Beauty’ 3) A. chinensis var. taquetii ‘Purpurlanze’ 4) A. simplicifolia 5) A. chinensis var. pumila 6) A. glaberrima saxosa 7) A. chinensis var. taquetii ‘Superba’ 8) A. ‘Straussenfeder’ 9) A. ‘Brautschleier’ 10) A. ‘Bronce Elegans’ On your next stroll through mountainous areas or woodlands in Asia and North America, keep your eyes peeled for splashes of colour in your undergrowth – you may well be looking at Astilbe. Or, much more likely, keep your eyes peeled for one of these fashionable plants next time you head to a garden centre! Astilbes are popular thanks to their colourful foliage that sometimes resembles heather, their dense blooms, and their propensity to do well when planted near water. Below we’ve rounded up a handful of popular Astilbe varieties to grow. If you’re keen to incorporate this plant into your outside space, these varieties should provide a helpful starting point. We’ve prioritised varieties in receipt of the Royal Horticultural Society’s Award of Garden Merit. This indicates suitability for growth in British gardens, meaning they’ll theoretically perform reliably and give you an easier time than some other options. All of the varieties in the list below should be grown in partial shade and in an exposed or sheltered location. 1) A. ‘Montgomery’ COMMON NAME(S): Astilbe ‘Montgomery’ HARDINESS RATING: H7 FLOWERS: Red FLOWERING SEASON(S): Summer FOLIAGE: Red and bronze SOIL PREFERENCE: Loam; Any pH SIZE: 0.5-1m in height, 0.5-1m spread With a dazzling bloom that sits on the threshold between crimson red and neon pink, ‘Montgomery’ is sure to catch the eye. With this variety, it’s easy to see where the heather comparison comes from. ‘Montgomery’ will be at its most colourful in summer, with the bloom fading through to winter. The foliage also lends a splash of colour throughout the year. For this variety, choose somewhere with loamy soil – ‘Montgomery’ will tolerate poorly-drained soil of any pH. Roy Nicol, a Professional Gardener and Master Horticulturist, states that: “‘Mongomery’ should be grown in part shade and south-facing aspects should be avoided.” 2) A. ‘Bressingham Beauty’ COMMON NAME(S): Astilbe ‘Bressingham Beauty’ HARDINESS RATING: H7 FLOWERS: Pink FLOWERING SEASON(S): Summer FOLIAGE: Green and bronze SOIL PREFERENCE: Loam; Any pH SIZE: 0.5-1m in height, 0.5-1m spread This Astilbe variety has proud pink plumage during the summer, making a shorter but dare we say it, bolder impression than ‘Montgomery’. The delicate flowers reward careful appreciation: lean in close to appreciate their gentle filigree. As with ‘Montgomery’, the ‘Bressingham Beauty’ variety likes loamy soil and will be fine in a poorly-drained spot avoiding south-facing aspects. 3) A. chinensis var. taquetii ‘Purpurlanze’ COMMON NAME(S): Chinese astilbe ‘Purpurlanze’ HARDINESS RATING: H7 FLOWERS: Purplish-red FLOWERING SEASON(S): Summer / Autumn FOLIAGE: Green SOIL PREFERENCE: Loam; Any pH SIZE: 1-1.5m in height, 0.1-0.5m spread ‘Purpurlanze’ translates from German as ‘crimson lance’ but, confusingly, you may also see this variety called purple lance, a name which does far more to capture the essence of the plant. This variety of Astilbe has, you guessed it, purple, lance-like panicles of flowers. Along with ‘Montgomery’, this variety showcases the beautiful colouration Astilbe is capable of contributing to your garden. Pink flowers are ten-a-penny, but the rich and deep red purples are fewer and further between. Select a spot with loamy soil, either well-drained or poorly-drained. Avoid a south-facing aspect for this variety, too. 4) A. simplicifolia COMMON NAME(S): Entire-leaved astilbe HARDINESS RATING: H5 FLOWERS: White FLOWERING SEASON(S): Summer FOLIAGE: Green SOIL PREFERENCE: Loam; Any pH SIZE: 0.1-0.5m in height, 0.1-0.5m spread This dwarf variety has a dalliance and dainty bloom of white flowers, giving a more subdued bloom than previous varieties we’ve seen, but, as with ‘Bressingham Beauty’, it’s a bloom that still rewards careful appreciation. Expect floral blooms about 30cm in height when this variety reaches maturity. The preferred conditions are the same as the previous two varieties we’ve seen. 5) A. chinensis var. pumila COMMON NAME(S): Dwarf Chinese astilbe HARDINESS RATING: H7 FLOWERS: Rosy-mauve FLOWERING SEASON(S): Summer FOLIAGE: Red and green SOIL PREFERENCE: Clay or loam; Any pH SIZE: 0.1-0.5m in height, 0.1-0.5m spread Another dwarf variety here, to give a bit of choice to gardeners looking for a plant to fill a small spot. The mauve flowers of the dwarf Chinese Astilbe are lovely, contrasting boldly with the rich green leaves they rise above. This variety will bloom in summer and will reach a max height of about 25cm at its peak. Conditions are familiar by this point: loam, well-drained or poorly-drained soil and any aspect except south-facing. “This plant will also tolerate clay soils,” share Roy. 6) A. glaberrima saxosa COMMON NAME(S): Smooth rock astilbe HARDINESS RATING: H5 FLOWERS: Pink and white FLOWERING SEASON(S): Summer FOLIAGE: Green SOIL PREFERENCE: Loam; Any pH SIZE: 0.1m in height, 0.1-0.2m spread Here’s an Astilbe variety that clocks in even smaller than the two dwarf varieties we’ve just been introduced to. This compact specimen will grow to a height of about 15cm, packing all of the features that make Astilbes so popular into a diminutive space. There are the vibrant leaves and the panicled blooms, and the summertime floral display to boot. Conditions here are familiar, too. Just note that this variety is less hardy than other varieties. This means that the minimum comfortable temperature for this variety is slightly warmer, around -15°C. This is still unlikely to be an issue in the UK, but it’s definitely worth knowing about. 7) A. chinensis var. taquetii ‘Superba’ COMMON NAME(S): Chinese astilbe ‘Superba’ HARDINESS RATING: H7 FLOWERS: Rosy-mauve FLOWERING SEASON(S): Summer FOLIAGE: Green SOIL PREFERENCE: Loam; Any pH SIZE: 1-1.5m in height, 0.1-0.5m spread We’ve had a couple of smaller varieties, so let’s go back to an Astilbe that stands tall and proud. ‘Superba’ lives up to its name, standing proud at around 1.5m off the ground at full height. This lofty stature means that ‘Superba’ flowers will wave alluringly above other flowers in your garden, rather than tucking themselves into, or even under, other displays. The green foliage and pink floral colouration are very distinctively Astilbe, as are its preferred conditions. This H7 hardy variety will do well in loam, well or poorly-drained soil, in south, west, or east-facing aspect. 8) A. ‘Straussenfeder’ COMMON NAME(S): Astilbe ‘Straussenfeder’ HARDINESS RATING: H7 FLOWERS: Pink FLOWERING SEASON(S): Summer FOLIAGE: Green and bronze SOIL PREFERENCE: Loam; Any pH SIZE: 0.5-1m in height, 0.1-0.5m spread Another tall Astilbe variety here: the ‘Straussenfeder’ reaches heights of around 1m, meaning its characteristic pink blooms can readily flaunt themselves and their pleasing bronze tint. This is a nice variety to have in your garden. No prizes for guessing its favourite conditions: loam, well or poorly-drained soil, no south-facing aspects. 9) A. ‘Brautschleier’ COMMON NAME(S): Astilbe ‘Brautschleier’ HARDINESS RATING: H7 FLOWERS: White FLOWERING SEASON(S): Summer FOLIAGE: Green SOIL PREFERENCE: Loam; Any pH SIZE: 0.5-1m in height, 0.1-0.5m spread Another Astilbe of German heritage here, with ‘Brautschleier’ translating as ‘bridal veil’ in English. Sometimes you come across a flower with a name so perfectly suited that all you can do is nod as you read it, and this is a fine example. The busily elegant white floral bloom brings to mind a bride in her dazzling wedding day dress, and it’s an aesthetic that can be put to such good use in any garden. Conditions are the same as the previous variety. 10) A. ‘Bronce Elegans’ COMMON NAME(S): Astilbe ‘Bronze Elegance’ HARDINESS RATING: H7 FLOWERS: Pink and cream FLOWERING SEASON(S): Summer FOLIAGE: Green and bronze SOIL PREFERENCE: Loam; Any pH SIZE: 0.1-0.5m in height, 0.1-0.5m spread The final Astilbe variety in our list is the ‘Bronce Elegans’ or, as it’s also commonly known, bronze elegance. This variety joins the other dwarves and compacts we’ve seen previously, and its name captures that characteristic bronze tint common to so many members of the Astilbe family.
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Use These 3 Aster Propagation Methods To Produce New Plants And Replace Old Stock
IN THIS GUIDE 1) Dividing Existing Plants 2) Harvesting And Growing From Seed 3) Taking Cuttings From An Existing Plant Asters, or Michaelmas Daisies as they are commonly known, are late flowering perennials that can bloom from the end of summer until the first frost, often as late as November. This article concentrates on Symphyotrichum novi-belgii asters, also commonly referred to as Michaelmas daisies. A stalwart of cottage garden planting schemes, they are a great and late source of nectar for pollinators to build up their reserves before winter arrives. Growing Asters by propagation is a rewarding and free way of producing new plants to replace old stock, add to your garden or give away. Propagating new Aster plants can be achieved by either: Dividing existing plants Harvesting the seed pods of the plant and growing from seed Taking cuttings from an existing plant Each of these processes is explained in more depth below. Difficulty Medium Equipment Required Gloves, spade, trowel, seed tray, pots, compost, knife, secateurs 1) Dividing Existing Plants As with many perennials, Asters tend to need to be rejuvenated every 3-4 years, which can easily be done through a process called division in early spring. Dividing Asters is an easy, quick and reliable way to produce more plants and is often the preferred option over growing from seed or cuttings. As soon as new green shoots appear in spring, an Aster can be dug up and lifted and divided into 2-3 smaller sections or divisions. Using a sharp spade or knife, the plant and its roots can be sliced apart into smaller clumps and any dead material removed. Each clump should reliably grow to be a healthy specimen, as long as each new division has roots and some fresh green growth showing. These divisions can then be planted out around the garden, potted up or given away to family and friends. 2) Harvesting And Growing From Seed Asters often self-seed around the garden and collecting their seed to sow is a viable way of propagating new plants. However, any plants grown from collected seeds may not be identical to their parent plant, unlike when grown from division or cuttings. Aster seeds can be harvested once the flowers fade and turn brown at the beginning of winter. On a dry day, the seed can be collected either by cutting off any spent flower heads or by crumbling the seed heads into an envelope or onto a dry surface. The collected material can often still be damp inside, so it is advisable to allow the heads and seed to dry out for at least 1-2 weeks before storing. Once completely dry, gently separate the seed from the rest of the plant material and label and store until the following year. To store the seeds, keep them in a dry, cool and airtight environment – brown paper envelopes or glass jars are ideal. Here in the United Kingdom, Aster seeds can be started indoors from March onwards. Sow the seed thinly in a seed tray or in modules, and cover lightly with compost and water well. Place on a warm window sill or in a propagator as Aster seeds need a temperature of 15-21°C to germinate reliably. Once germinated, usually after 2-3 weeks, and large enough to handle, carefully prick out and pot on individually in small pots. Grow on and once the risk of frost is over, harden off and plant out in their final growing place. 3) Taking Cuttings From An Existing Plant As with dividing, basal softwood cuttings from Asters will come true to their parent plant. In spring once new growth appears, using a clean and sharp pair of secateurs or knife, take some cuttings approximately 8-10cm long. Take the cuttings as close to the base of the plant as possible, including some of the harder wood basal growth. Remove all but the top few leaves of the cuttings and lightly cover the bases with a rooting hormone. Insert the prepared cuttings into a pot pre-filled with a cuttings compost mix, so that the leaves are above, but not touching the soil and water in well. Place the cuttings in indirect light in a propagator or cover them with a clear plastic bag and keep them warm indoors to increase humidity. Keep the soil moist and once the cuttings have rooted, usually after 2-4 weeks, pot on individually and grow on. Harden the new plants off and plant out when large enough and only once all risk of frost has passed. “You will normally find that Symphyotrichum asters grown from seed will put on leaf growth in the first year and flower in the second year, whilst plants from cuttings and division will normally flower in the same year,” shares Dan Ori, Horticultural Instructor and Consultant.
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Asters Looking Less Impressive Over Time? It's Time To Divide And Transplant
IN THIS GUIDE 1) Dig Up Your Aster 2) Divide The Roots 3) Prepare The New Spot 4) Plant The Divisions 5) Ongoing Care Asters bring vibrant bursts of colour each autumn but have a tendency to become leggy and produce less impressive blooms over time. If that happens, it’s time to divide and transplant. They prefer a spot which receives 6-8 hours of direct sunlight per day, with well-drained soil and a sheltered aspect. However, it’s not the most demanding perennial you’ll encounter and can be easily transplanted if you follow these steps: Dig up your Aster plant in springtime. Divide its roots using a sharp tool. Prepare the new spot for planting. Plant the newly created divisions. Care for each of your plants as they re-establish themselves. Each of those steps is discussed in more detail below to make the process as simple and as straightforward as possible. Difficulty Easy Equipment Required Spade, soil saw, all-purpose fertiliser, organic mulch Preferred Aspect Full sunlight, sheltered 1) Dig Up Your Aster The best time to propagate your Aster plant is in spring after the worst of the cold has passed. That’s because young, newly divided plants are particularly susceptible to frost. Carefully dig up the entire plant, taking care to excavate as much of the root system as you can without damaging it. If you do need to cut the roots, take care to keep the incisions clean and distanced from the main root ball. 2) Divide The Roots With the root ball excavated, if you wish you can now likely split it into 3-4 different segments. It’s advisable to use a soil saw or the sharp end of your spade for this since you want the cuts to be as clean as possible. Once you have separated out your original Aster into offshoot plants, gently shake excess dirt from the separated specimens. 3) Prepare The New Spot While your Aster might survive in the shade, it will produce better blooms in full sunlight. Select a location which receives plenty of sun and dig a separate hole that is the same size as the original one for each division, turning the soil to ensure aeration and drainage. You may wish to mix in compost, animal manure or super phosphate with the soil. This can give the plant the best chance of flourishing but is not strictly necessary. 4) Plant The Divisions Carefully place the divisions in their respective holes, gently filling the area around them with soil. They should stand upright but not be packed in too tightly. When selecting a location for the new divisions, make sure that you give adequate space between them for their roots to develop. Around 15-20cm is advisable for smaller Asters and up to 30cm for giant-sized specimens. 5) Ongoing Care Administer a dose of all-purpose fertiliser to the divisions to help them bed in, topping off with organic mulch to insulate the plants from bugs and other pests. You should also water them thoroughly upon planting, with enough water to make the soil moist but not drenched. Once the Aster has become established, there is no need to water them except in times of drought. However, a second application of fertiliser a month after transplanting will help their development, but don’t expect flowers to appear for a year or two.
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Growing Coleus 'Painted Nettles' For Jungle-Style Planting From An Indonesia Native
IN THIS GUIDE Overview Coleus Varieties Planting Plant Care Container Growing Propagation Frequent Growing Problems References Coleus, also known as Solenostemon scutellarioides, is a popular ornamental houseplant which can be grown outdoors during the summer in the UK. In this guide, you will learn more about this attractive foliage plant, and how to grow it and take care of it year-round. Native to Indonesia, this plant is part of the family of mint.1 Overview Botanical Name Coleus scutellarioides Common Name(s) Painted Nettle Plant Plant Type Perennial Houseplant Native Area Indonesia Hardiness Rating H1C Foliage Evergreen Flowers Blue When To Plant May-June When To Prune September This species has been categorised as Plectranthus, then as Solenostemon, but is now considered to be part of the expanded Coleus genus.2 This plant is also known by the common name painted nettle. This reflects its relationship to Dead Nettles which are also in the mint family.3 Coleus Varieties Varieties of C. scutellarioides which have RHS Awards of Garden Merit are: ‘Balcenna’ ‘Black Prince’ ‘China Rose’ ‘Combat’ ‘Crimson Ruffles’ ‘Gay’s Delight’ ‘Juliet Quartermain’ ‘Lord Falmouth’ ‘Picturatus’ ‘Pineapple Beauty’ ‘Pineapplette’ ‘Pink Chaos’ ‘Redhead’ ‘Roy Pedley’ ‘Royal Scot’ ‘Trusty Rusty’ ‘Walter Turner’ ‘Winsome’ ‘Wisley Tapestry’ Planting Painted nettles are popular for summer bedding schemes and for exotic, or jungle-style planting schemes, and are commonly grown as houseplants or in conservatories in the UK. Though perennials, they are often grown as annuals when grown outside in temperate climes, though they can also be kept year-on-year if protected from frost and cold and brought inside for winter, or grown inside year-round. Purchase coleus plug plants in early spring and grow them indoors until after the last frost date in your area, or when the weather has warmed. The best time to plant out is in May or June, once the weather has reliably warmed and there is no risk of frost. Be sure to harden off plants grown indoors before they are planted out so that they become accustomed to outdoor conditions. If growing coleus outside, it is important to choose a suitable spot. They can work well in a garden border, alongside other summer bedding plants and also look nice in containers. Details of where to place coleus, outside and indoors, are provided later in this guide. Growing From Seed Coleus can be grown from seeds planted under glass in early spring. However, it should be noted that cultivars may not come true. Usually, coleus is purchased as a plug plant, summer bedding plant, or as a houseplant. Plant Care Light levels and water are the most important considerations when growing and caring for coleus. Get these things right and you should not find this too challenging a plant to grow. Light & Temperature Coleus is a tender plant which cannot cope with temperatures below 5-10°C. It can either be grown inside year-round or placed outside in a sheltered spot during the summer months. Coleus like a position in full sun or partial shade, and will do well indoors in a reasonably bright location, which gets a little bit of direct sun. Coleus’ colourful foliage will be at its best when they have some light or dappled shade, but they do need some bright light each day, whether grown indoors or outside. A south or east-facing aspect with morning sun can be ideal. Soil These plants require moist but well-drained soil or growing medium, though are unfussy when it comes to the specific type or soil pH. When growing in pots or containers, a high-quality loam-based potting mix will be ideal. Whether growing in the ground or in pots, ensuring adequate moisture while also making sure there is free drainage is the balancing act that you have to tread. Watering Water moderately, aiming to keep the soil or growing medium moist throughout the growing season. Do not allow the soil or growing medium at a depth of around 5cm below the surface to dry out. Watering needs will be lower over the winter months indoors. Coleus typically like a high humidity level, so mist regularly if the air inside your home is dry, so mist regularly if the air inside your home is dry. Feeding Coleus does not usually require additional feeding. However, if the plant seems lacklustre, you can feed during the growing season with an organic liquid plant feed suited to houseplants when growing in pots. Pruning Pinching out the growing tips of the plant in summer can encourage bushiness. The plants can also be pruned back when bringing outdoor-grown specimens back indoors in early autumn. Overwintering Coleus used as summer bedding can be lifted and placed into pots to bring inside in September. Alternatively, cuttings can be taken in summer to propagate the plants. Container Growing Growing coleus in pots, either indoors or placed on a patio during the summer and brought inside in winter, can be a good idea. Choose a pot which retains moisture relatively well, but drains freely. Fill with a peat-free, loam-based potting mix. Potting & Repotting Typically, coleus will grow to a size allowed by the pot size. Trim back outside grown specimens of coleus if required at the end of the summer season outdoors, so it will be comfortable in the same pot, or choose a somewhat larger pot to accommodate the plant as it grows. Propagation Taking coleus cuttings in summer is a relatively easy way to produce new coleus plants which are clones of the parent plant. “If I want to keep your coleus for the following growing season, I find the easiest way to do so is to take cuttings in late summer and keep them as rooted cuttings in a warm greenhouse or bright window sill over winter before potting on the following spring,” shares Colin Skelly, a Horticultural Consultant. “This will save space for storing larger plants and provides vigorous young plants for re-planting.” Bear in mind, as mentioned above, cultivars do not always come true from seed. Softwood cuttings of coleus root relatively easily, though you can use a rooting hormone to improve success rates if you wish. Place cuttings in a glass of water, or in a moist yet free-draining medium, around the edges of a pot to root. Then once strong roots have formed, place each cutting into its own pot to grow on. Frequent Growing Problems Coleus growing outside in summer is rarely troubled by pests and disease. Indoors, like other houseplants, coleus can experience problems such as whitefly, scale insects or mealybugs. Legginess Indoor-grown coleus may become leggy if it does not receive adequate light. You can also cut back growing tips in summer, perhaps taking cuttings for propagation, to keep the plant bushier. Flowers can also be pinched off if you wish to encourage plants to put their energy into foliage growth. Saving A Damaged Coleus If your coleus plant does not seem to be thriving or even looks like it is dying, all is not necessarily lost. In certain circumstances, you may be able to revive your plant. If your plant is wilting, the first thing to check is that you have watered it enough. If the soil or growing medium is dry, watering may be enough to bring it back to good health. Unfortunately, you may not be able to save your plant if it is suffering from root rot or frost damage, so make sure you meet the plant’s environmental needs and care for it as discussed above to keep it happy, healthy and attractive over the years to come. References 1. Coleus | plant. (2023, March 6). Encyclopedia Britannica. Retrieved March 14, 2023, from https://www.britannica.com/plant/coleus 2. Paton, A., Mwanyambo, M., Govaerts, R., Smitha, K., Suddee, S., Phillipson, P. B., Wilson, T., Forster, P. I., & Culham, A. (2019). Nomenclatural changes in Coleus and Plectranthus (Lamiaceae): a tale of more than two genera. PhytoKeys, 129, 1–158. https://doi.org/10.3897/phytokeys.129.34988 3. Red dead-nettle. (n.d.). The Wildlife Trusts. Retrieved March 14, 2023, from https://www.wildlifetrusts.org/wildlife-explorer/wildflowers/red-dead-nettle
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Salvia ‘Hot Lips’: Here's Where Experts Say To Plant Yours For Optimal Results
IN THIS GUIDE Overview Planting Guidelines Plant Care Propagation Companion Planting Common Problems References With their extravagant colourings, reliably long blooming seasons and evergreen foliage, Salvia ‘Hot Lips’ are hot property in summer gardens and ornamental borders. Not just a pretty face, ‘Hot Lips’ will also entice plenty of bees and butterflies into your home through its intoxicating nectar. The aroma given off by its blossoms is irresistible to humans too, so plant it near a bench or path to take full advantage. Best of all, it’s easy to cultivate and fairly hardy against the British winter, so it’s an ideal option for beds, borders or any other spot in your garden that you wish to liven up with some energy and activity. Overview Botanical Name Salvia x jamensis Common Name(s) Salvia ‘Hot Lips’ Plant Type Perennial Shrub Native Area North America Hardiness Rating H5 Foliage Evergreen Flowers Large, open-mouthed racemes of red-and-white bicoloured petals, which can be entirely red or white in some climates When To Plant May-June When To Prune September-October ‘Hot Lips’ is a member of the salvia genus, which is also known as ornamental sage and is prized for its extensive blooming periods and vibrant colour palette. It is a particularly spicy specimen, with its open-mouthed petals a beautiful combination of red and white. At certain times of the year or in certain regions of the country, you may notice that the flower is entirely one colour or the other, though a mixture is more common. In any case, it’s a great addition to almost any location you place it, often acting symbiotically with other plants to prevent blights such as black spot and mildew. What’s more, its status as a member of the sage family means its foliage and flowers are actually edible and are sometimes used as a garnish for salads, cocktails or other dishes and drinks.1 Some people say its taste is slightly reminiscent of blackcurrant, though you might have to use a little bit of imagination to arrive at that conclusion. Planting Guidelines As its name suggests, ‘Hot Lips’ performs at its best when the temperature rises. It’s not overly fussy about the soil used as long as it’s moderately fertile and has good drainage. Plant in a hole deep enough to submerge the root ball if transplanting from a pot. Space plants at least 30cm apart to allow the roots to develop properly. Hardiness ‘Hot Lips’ is generally hardy enough to survive the British winter, though it may succumb to frost in particularly cold years. Insure against that by taking cuttings at the end of summer or taking potted specimens indoors when the mercury drops. Preferred Aspect ‘Hot Lips’ prefers as much sun as possible, so plant it in a south-facing aspect in a sheltered location. Partial shade may be tolerable but is not advisable. The front or middle of garden borders is the best place for it. Soil Requirements The plant isn’t too demanding with regards to the type or acidity of the soil it’s planted in, though good drainage is a must. It doesn’t enjoy getting its feet overly wet or dry, so take precautions to ensure it’s never waterlogged or parched. Plant Care Most varieties of salvia will survive just fine without too much in the way of TLC, though particularly cold parts of the country can spell trouble for them. Just follow the guidelines below and you should enjoy an impressive display of blooms year after year. Winter Care If you live in an extremely cold and wet part of the British Isles, it’s good practice to use horticultural fleece or organic mulch to insulate the roots. Alternatively, you can just bring potted plants indoors during the colder months. “If you live in a cold part of the country, you can also dig up plants growing in the ground in autumn before the first frosts and either divide or pot the whole clump into a large pot,” shares Colin Skelly, a Horticultural Consultant. “Water well, cut back the foliage and keep in a cold greenhouse over winter. It will be ready to plant back outside the following late spring.” Pruning Strictly speaking, it’s not 100% necessary to prune salvias at all. If you are going to do so, it’s advisable not to prune too early, since this could jeopardise the plant’s survival in the case of a harsh frost. Instead, wait until it has begun to show new growth in spring before pruning back by a third. In blooming season, be on the lookout for wilted blooms to deadhead in order to encourage longer and more prolific flowering throughout the entire period. Propagation As mentioned above, it’s a good idea to take cuttings to provide insurance in case it falls victim to a severe winter. You can do so in spring before it flowers with softwood tip cuttings or in late summer with semi-ripe cuttings. Whichever type you favour, it’s best to take the cutting in the morning when the plant is at peak hydration. Select a healthy stem and cut just above a leaf node, aiming for the cutting to be around 5-10cm in length. Dip the cut end of the cutting into the rooting mixture and plant it in a 15cm pot filled with compost and perlite. Cover with a plastic bag and keep warm and moist for the first few weeks of its life, until it has begun to take root. Companion Planting Salvia ‘Hot Lips’ will look incredible alongside any flowering perennial border plants, with alliums, antirrhinums, dahlias, echinacea, penstemons, rudbeckias and verbenas just some of the options on offer. Underplanting them alongside roses makes for another complementary display since the salvias will begin flowering just as the roses finish. Meanwhile, you could also pair them up with other salvia cultivars, such as S. greggii ‘Royal Bumble’ or S. ‘Dyson’s Joy’. Common Problems Salvia ‘Hot Lips’ is generally disease-free and can even ward off potential blights from neighbouring plants. However, its aesthetic qualities mean it is a common target for pests such as leafhoppers, rosemary beetles, slugs and snails. References 1. Ask Mr. Smarty Pants. (n.d.). Lady Bird Johnson Wildflower Center – the University of Texas at Austin. Retrieved March 24, 2023, from https://www.wildflower.org/expert/show.php?id=5859
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