Growing
Growing Mexican Fleabane - A Mat-Forming Perennial Ideal For Dry Gardens
IN THIS GUIDE Overview How To Grow Erigeron Ongoing Plant Care References Mexican Fleabane is a mat-forming perennial that is great for dry gardens and wildlife attractions. Learn more about this plant and how to grow and care for it in this guide. If you have a garden that tends to dry out or a tricky sun-baked spot, Mexican fleabane, Erigeron karvinskianus, could be an excellent choice for a resilient and fairly drought-tolerant ground-cover plant. It looks wonderful in a rock garden, creeping down the side of stone or brick steps, in cracks on walls or along pathways, and can also suit container growing. “I love adding ornamental plants like Erigeron karvinskianus, which flowers all summer long, into my container displays,” shares The Bonnie Gardener, Nicola Macnaughton. Overview Botanical Name Erigeron karvinskianus Common Name(s) Fleabane, Mexican Fleabane Plant Type Perennial Native Area Mexico Hardiness Rating H5 Foliage Deciduous Flowers Daisy-like When To Plant May-September When To Prune September-October Mexican fleabane is a deciduous flowering perennial in the Asteraceae plant family.1 It is native to Mexico and other parts of Central America and has naturalised in a number of other locations around the world.2 The plant grows from woody rhizomes, spreading out to form mats of hairy, narrow leaves from which daisy-like flowers around 1.5cm wide emerge. Like lawn daisies, these flowers open with white petals, but they soon develop a pinkish-purple tinge. How To Grow Erigeron E. karvinskianus can be purchased and planted out any time between May and September. It can be placed into planting pockets in a stone wall, in the crevices between paving or used as part of a rockery or other dry-zone planting scheme. “Erigeron karvinskianus looks really good tumbling down steps or over a wall,” shares Horticultural Consultant Colin Skelly. “Once established it will readily self-seed and the challenge is to edit where you allow it to persist. “Large clumps can be trimmed in early spring to shape and control their growth.” It can also work very well in window boxes or other containers. However, this plant is also relatively easy to grow from seed which is a cheaper and more eco-friendly option than purchasing young plants in plastic pots that are often grown non-sustainably in peat potting mixes. Growing From Seed The seed of Mexican fleabane can simply be directly sown where it is to grow in the spring. Scatter the seeds in March or April into the areas of soil between gravel, stones, rocks or paving where you would like them to grow. Germination will typically take around 2-3 weeks. Until they begin to form roots, you can also grow them in a cold frame and then transplant them once they establish themselves. You can also coat seeds in a small amount of clay and press these into gaps in walls so they can grow and spread over the vertical surface from there. Ongoing Plant Care When grown in a suitable spot, Mexican fleabane is a very easy and trouble-free plant to care for. In fact, where it is very happy, it should be noted that it will self-seed readily and can potentially become invasive, so this is something to consider before you decide to include it in your garden. Aspect A south-facing spot will often be ideal, but west or east-facing aspects can also suit this plant. Light & Temperature The plant prefers full sun but in particularly scorching spots, it will love a little midday shade. Soil Mexican fleabane can be wonderful for any free-draining soil that is moderately fertile and unfussy about soil pH. Although the plant is great for drier locations, it will do best in soil or another position that does not entirely dry out in summer. Fertiliser Feeding this plant will not usually be required. However, if the growth seems weak, organic liquid fertiliser can be used every month or so in spring and summer. Water & Humidity Though these plants like free-draining soil, it is best to water consistently throughout the summer months. Let the plant dry out between waterings, but if there is a prolonged dry period, be sure not to let it go thirsty for too long or it may wilt. Remember that when growing in pots you will likely have to water more frequently. Container Growing & Repotting Mexican fleabane is great for free-draining containers or window boxes in a sunny spot. Simply fill your container with a suitable, free-draining medium and scatter the seeds over the top in spring, and you should be rewarded with a profusion of flowers from May right through to September. As a relatively slow-growing plant, Mexican fleabane should not require repotting too frequently. Ideally, repot or transplant container-grown plants when the weather is not too hot and dry. Pruning & Deadheading You can deadhead the flowers to promote continued flowering, though this is not really necessary. In autumn, if the plants are looking straggly, you can also cut back the stems to just above the ground if they do not die back naturally themselves. Overwintering The plants will remain dormant over the winter months, dying back in all but the mildest areas, and new growth should emerge in spring. Propagating Once you have some Mexican fleabane growing in your garden, you can easily propagate new plants, either by collecting and sowing the seed or by dividing established clumps. As with seed sowing, division is best done in the spring. Remember that in many gardens, this plant may also self-seed prolifically. Common Problems Generally, you will find that you will not experience many issues with this plant as it is not typically troubled by pests or diseases. Most problems with die-offs arise because the spot is too damp, or winter waterlogging has occurred. Companion Planting Plants that work well with Mexican fleabane include: Erigeron ssp. Armeria Campanula portenschlagiana Globularia Lithodora diffusa Phlox douglasii Saxifrages Sedums Thymes Veronica umbrosa References 1. Mexican Fleabane (Erigeron karvinskianus). (n.d.). iNaturalist. Retrieved March 15, 2023, from https://www.inaturalist.org/taxa/76923-Erigeron-karvinskianus 2. Mexican Fleabane – Erigeron karvinskianus. (n.d.). Brickfield Park. Retrieved March 15, 2023, from https://www.brickfieldspark.org/data/mexicanfleabane.htm
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Vinca Minor (Periwinkle) Is An Excellent Set-And-Forget Plant To Help Suppress Weeds
IN THIS GUIDE Overview Is Vinca Minor Invasive? Common Varieties Sowing From Seed Planting Periwinkle Plant Care Getting Rid Of Periwinkle References Vinca minor, more commonly known as ‘Periwinkle’, is a low-growing perennial that’s widely used as weed-preventative ground cover. An extremely tough customer, it requires very little in the way of upkeep or maintenance, making it an excellent choice for set-and-forget corners of the garden. Its ability to thrive in low-light conditions and tolerate drought with ease makes it an ideal option for planting underneath trees or in shady alcoves where nothing else seems to grow. The evergreen nature of its foliage provides colourful intrigue throughout the calendar year, while the bright blossoms in spring and summer are an additional plus. Overview Botanical Name Vinca minor Common Name(s) Common Periwinkle / Lesser Periwinkle / Myrtle / Dwarf Periwinkle Plant Type Perennial Native Area The Mediterranean and Southern Europe Hardiness Rating H6 Foliage Evergreen Flowers Blue, purple or white flowers rotating out from a yellow stamen When To Plant Spring or autumn When To Prune August-November A native of the sultry climes of southern Europe and the Caucusus, Vinca minor has adapted remarkably well to the less predictable and hospitable weather in the UK.1 It’s a common sight in parks and even graveyards around the country today, while its ease of cultivation makes it a popular choice for green-fingered enthusiasts too. Is Vinca Minor Invasive? V. minor is a very vigorous and resilient grower and will require little to no maintenance from your side in order to continue thriving. In fact, my primary recommendation when caring for this plant would be to keep it from growing too vigorously and overstepping the mark. Having said that, the plant is fairly easy to control and is not considered invasive here in the UK. Vinca major – or greater periwinkle – is another kettle of fish entirely. This species is extremely invasive and will encroach on the territory of any neighbouring plants in its vicinity since it has a tendency to send down roots wherever its stems touch the soil.2 As a result, it’s highly advisable to ensure you are indeed planting V. minor (and not V. major) in your garden. Common Varieties The RHS Plant Finder lists 80 different forms or cultivars of V. minor. Most send forth bluish-purple flowers each spring and summer, but there are others which offer up lavender or even white blossoms as well. Here are some of my personal favourites: V. minor ‘Atropurpurea’ This variety produces bright green foliage and is complemented by a deep reddish-purple hue to the flowers, which makes for an extremely eye-catching package. V. minor f. alba ‘Gertrude Jekyll’ There’s a delicious contrast between the dark tones of the green leaves and the brilliant whiteness of the floral blossoms on this showstopper. V. minor ‘Illumination’ The variegated foliage on this specimen contrasts green with veins of gold, while the striking blue flowers add even greater appeal. V. minor ‘Variegata’ As the name suggests, this is another option with variegated foliage and blue flowers, though this time green is blended with creamy white on its leaves. Sowing From Seed Growing V. minor from seed is possible, but it’s a trickier affair than propagation via division or from nursery plants. That’s due to the fact that you’ll need to give the seeds extra care in their first few months of life and because they grow more slowly from seed. Having said that, it’s perfectly feasible to sow periwinkle seeds if you’d prefer to do so. Begin by filling a seed tray with a potting mixture and watering the compost thoroughly so that excess liquid drains from the bottom. Place 3-4 seeds in each cell and cover them with 5mm of soil, then firm down gently and mist. Cover the seed tray with a black plastic bag to retain moisture but block out direct sunlight, then place it in an area which enjoys a stable temperature of around 25°C – you can use a heat mat or other apparatus if necessary. After germination has occurred (normally within 1-2 weeks), remove the plastic bag and place the tray on a sunny windowsill. Keep the soil moist and fertilise with a standard fertiliser after around 10 days. Thin out the seedlings in each cell, keeping only the most healthy, and transplant them to their own pot around 10cm in diameter once they have reached a height of 8cm and show leaves. Feed with fertiliser once more after a fortnight. Planting When the plant is big enough to transplant outside, dig a hole big enough to fit the root ball and place it gently into it, then fill in the excess area with soil and water thoroughly. If you are not planting from seed (but from division, for example), simply cut off a section of the desired plant, ensuring that the root ball is big enough to survive on its own. Ensure that cuttings are kept at least 30cm apart to give them enough room for their roots to fully develop and voila! Your periwinkle will become self-sufficient in next to no time. You can use more than one seedling to cover a larger area, but be mindful that a single modestly sized plant is capable of spreading up to 2m in diameter. Periwinkle Plant Care Generally speaking, periwinkles are extremely easy to care for, which is why they’re so popular across the British Isles. Aspect For the best results, you should plant V. minor in a partially shaded area of the garden. However, one of its strongest qualities is its ability to do well in darker spots. However, avoid exposing it to direct sunlight as it may burn and die. Preferred Soil Periwinkle prefers soil that is fertile and well-draining, but again, it’s unfussy in this aspect and will accept almost any soil type. If you do find that your garden is home to particularly difficult terrain, you can improve it by adding mulch or well-rotted organic matter to the soil prior to planting. Watering Periwinkle is fairly drought resistant and won’t require much in the way of irrigation after its initial planting. This is why I like to use it as a ground cover underneath trees and other taller plants since its roots won’t compete for moisture or inhibit their growth. Pruning Pruning periwinkle is entirely optional. However, its fast-growing nature means you may want to keep it in check so that it doesn’t disrupt the harmony of your garden. If you are going to prune, I recommend that it’s best to do so once the final blooms of the season have begun to fade, which normally occurs in late summer. Common Pests The most common afflictions affecting periwinkle are the same ones which you will likely have experienced with many other garden plants. That includes all manner of creepy crawlies, including aphids, scale, spider mites and whiteflies. An application of neem oil or (preferably organic) insecticidal soap usually does the trick. Meanwhile, fungal diseases such as botrytis blight can also be a problem from time to time, with the most notable symptoms including leaf spots, wilting and dieback. You can avoid this problem from occurring by focusing on the soil rather than the foliage when watering the plants, as well as improving air circulation by thinning out the leaves and leaving enough space between plants. Companion Planting Because it’s a drought-resistant plant, V. minor plays well with most others and there are no specific specimens that I’d recommend to accompany it. However, a favourite planting location for me is underneath a garden tree, since most plants will struggle to thrive in the shade thrown by the canopy. “I tend to use Vinca minor if the object is purely ground cover to suppress weeds in an area (particularly dry shade),” shares Master Horticulturist Colin Skelly. “Its tendency to spread inexorably (though not as aggressively as V. major) means that it doesn’t associate well with a mixed perennial planting.” Its ease of cultivation and spreading tendencies also make it ideal for filling out a barren stretch of a rockery or flower bed. Just be careful that it doesn’t step on the toes of any neighbouring flowers in the vicinity. It’s also important to ensure that the location is right before planting since it’s difficult to uproot after the fact – but more on that in the next section. Getting Rid Of Periwinkle While periwinkle can be tricky to get rid of once it has taken hold, it is possible, especially when dealing with V. minor. Using a hand trowel, unearth all parts of the plant you wish to remove, including the entirety of the root ball, and then dispose of it in garden waste bags rather than dumping it on the compost heap. This latter step is especially important if it’s V. major rather than V. minor you’re handling, as the former can send down new roots even when unearthed. Only use a weedkiller as a very last resort, since contamination of any plants in the vicinity will kill them off, too. Apply to the leaves and let them suck the poison down into their roots. How Quickly Does Periwinkle Spread? Although V. minor is not as rapid as V. major, it will still spread fairly quickly once it is established. If planting from seed, you should have patience and expect things to progress slowly for the first couple of years. However, after that, or if propagating via division, the periwinkle will cover an area of up to 1m or more in a single year. References 1. Vinca minor. (n.d.). Kew Royal Botanic Gardens. Retrieved March 22, 2023, from https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:82701-1 2. Vinca major. (n.d.). Plant Right. Retrieved March 22, 2023, from https://plantright.org/invasive/vinca-major/
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How Experts Prune Their Lavender Annually To Prevent Them Getting Too Woody
IN THIS GUIDE Do You Need To Prune Lavender? When To Prune Lavender How To Prune Lavender Lavender is a great choice for many gardens, as it is not only a beautiful flowering plant but also a useful herb. Lavender is not usually challenging to grow, and as long as you choose the right spot to grow it in, it is low-maintenance and requires little care. However, to keep lavender happy and healthy, it is best to prune your lavender plants (at least lightly) every year. “How to prune lavender is one of the questions we get asked most often,” explains Julia Snowball, the Head Gardener at Yorkshire Lavender. When it comes to pruning lavender, this guide explains all you need to know. Difficulty Easy Equipment Required Secateurs When To Prune August-September Do You Need To Prune Lavender? “Pruning lavender is the best way to keep them looking fresh and healthy and to avoid them getting too woody,” says Nick and Lyndsay Butler, owners of Lavender Fields, a specialist farm based in Hampshire. Woody stems tend to look less attractive, and there will be less green growth over time, flowering will be reduced and the plant won’t look as good. Furthermore, woody lavender plants are more likely to suffer frost damage or damage due to waterlogging. By pruning your lavender plants, they won’t get woody as quickly and will stay green, healthy, resilient and flexible for longer. A woody and straggly lavender bush is usually best replaced since lavender won’t regrow well from older wood. When To Prune Lavender Lavender is best pruned annually, as Julia shares: “Lavender bushes should be pruned annually to stop them becoming large and woody. “I recommend pruning after flowering, but you should definitely not prune any later than mid-September.” Usually, you should only remove a little material and not hard prune back to wood. “Trimming the plants once a year is also essential for long life and good flowering,” shares Charlie Byrd, owner of Cotswold Lavender. “Cut at the end of the summer to allow the plants time to recover before they go dormant for the winter.” We’d recommend carrying out this job in August or in September, once the flowers have finished blooming on the plant. “However, for later flowering lavenders, including Lavandula x intermedia like ‘Old English’, you should cut back the following spring,” says Julia. To determine exactly when to prune, look at the flowers of the lavender plant. By this time, they should be dull and grey and bees and other insects will no longer be buzzing around them. When most of the flowers change in this way, this is the best time to prune. How To Prune Lavender The actual process of pruning lavender is very simple. Take some clean, sharp secateurs and remove the flowering stems, then cut back the current season’s growth while ensuring that at least a little fresh growth remains. “Prune all English Lavenders in the same way,” explain the Butlers. “English varieties should be pruned to about 2-3cm above the woody stems of the plant. “This may look harsh, but it will keep the plant healthy and ensure you retain the nice tight shape of the plant.” “Always ensure that there are green shoots below where you cut,” adds Julia. With English lavender, you can be more vigorous in cutting back than you can with other types and should not be excessively tentative if you want your plant to stay healthy and attractive for as long as possible. Personally, I like my lavender to look less clipped and more natural. A more organic look works better on a forest garden fringe, in a wildlife-friendly area, or in a natural-looking cottage garden. Since my lavender is on the sunny edge of my forest garden, I prune only lightly. If you prefer a formal, neat or contemporary look, you might like to prune back harder and keep a more neat and clipped appearance to your lavender, as long as you don’t cut back too hard. “Don’t cut into woody material,” Charlie warns. “They really don’t like that at all and will often die as a result.” Of course, a neater look might also suit you if you are creating a lavender hedge and don’t just have stand-alone plants. As you can tell from the above, pruning lavender is indeed a fairly simple process. Just remember not to prune back too hard to old woody growth, and in all honesty, you cannot go too far wrong. A light prune each year will keep your lavender healthy and growing strong and it should flower well for you over a number of years.
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Deadheading Ranunculus Can Help Them Bloom Better - But Careful Not To Prune Too Hard
IN THIS GUIDE Deadheading Pruning Ranunculus is a varied genus incorporating a wide range of flowering plants, commonly known as ‘buttercups’. Many buttercups may grow in UK gardens, including native options like meadow buttercups, and common weeds or wildflowers like creeping buttercup. These are low to no-maintenance plants, which require minimal care in British gardens. As gardeners, however, there are a number of other ranunculus varieties that you might choose to cultivate, which do require a little more care. The most popular of the non-native ranunculus is Ranunculus asiaticus, also known as the ‘Persian Buttercup’, or ‘Garden Ranunculus’. These are popular florists’ flowers, commonly chosen for weddings and other special events and they look wonderful in the garden but are also excellent as cut flowers – with good longevity once cut. Difficulty Easy Equipment Required Secateurs or gardening knife When To Prune Remove spent flowers as and when they appear Deadheading Most garden ranunculus will bloom for longer and more prolifically if you deadhead the spent blooms. This will encourage the plants to put their energy into flower production rather than on producing seeds. If you are not interested in collecting seeds to sow, deadheading can improve your flowering displays and give you more cut flowers for your home. To deadhead ranunculus, simply snip off any stems that have finished flowering, or spent blooms on branching types, using clean sharp secateurs or a gardening knife. Of course, if you cut flowers for displays inside your home, then you may not need to deadhead at all. “Whilst for some plants, I recommend taking a little more growth off whilst deadheading to keep them compact, this is simply not the case with Persian Buttercups,” shares Master Horticulturist Peter Lickorish. “Slicing cleanly to where a flower stem joins another or to a leaf is all that is required whilst flowering. “After flowering, wait another six weeks as a minimum, before cutting plants to ground level ahead of their dormant period, if you decide to do this.” Pruning Other than deadheading, ranunculus does not typically need to be pruned or cut back at all. It is important to leave the foliage in place after the flowering has finished, as this foliage is still collecting energy which will be stored in the tubers over the dormant period and will allow for strong healthy growth and good flowering the following year. Once the foliage has died back naturally, you can cut this right back to the ground. However, it is generally best to leave this in place for the wildlife in your garden or to offer some protection from the cold to the tubers when growing in cooler regions or when growing in pots. Some people will choose to lift the tubers over winter, to store them in a cool, dry place. If you are doing so, you will cut the foliage back before you lift the tubers, but in most cases, this is not necessary and you can leave the plants in a suitable spot (in a greenhouse, polytunnel or a dry and sheltered spot outdoors).
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Why Ranunculus Grow Best In Containers: They Love Free Draining Conditions
IN THIS GUIDE Are Ranunculus Suited To Pots? Choosing Suitable Containers Compost For Ranunculus Potting Up Ranunculus Container Ranunculus Care Though there are many Ranunculus species, many use the term ranunculus to refer to Ranunculus asiaticus, also known as ‘Persian Buttercup’ and sometimes simply referred to as ‘Garden Ranunculus’. These plants are popular for their stunning flowers that come in a range of hues and there are a number of different varieties to consider. These flowers can look great in a sunny and sheltered spot in the garden, or when used as cut flowers in displays. They are extremely popular for weddings and other special events. Are Ranunculus Suited To Pots? Unlike our native buttercups, and other ranunculus plants commonly grown in more wild, organic and natural-style gardens, these ranunculi are more tender. They are often cultivated in containers, sometimes in a sheltered and sunny spot outdoors, but more commonly, in the UK, in an unheated greenhouse. In short, yes, you can grow garden ranunculus in pots. In fact, this is the best way to grow them. There are also other ranunculi that can work well in containers, including alpine varieties, but in this article, we’ll focus on the popular florist flowers – Persian buttercups. Choosing Suitable Containers One of the reasons that these ranunculi grow well in containers is that they enjoy free-draining conditions. Containers can often provide free-draining conditions more effectively than in-ground growing, especially where there is heavier or clayey soil. When choosing a container for these and any other plants that like free-draining conditions, it is important to choose one which will allow excess water to drain away freely. You should make sure that there are drainage holes at the base and should also consider using feet to keep pots up and off the ground. Terracotta pots can be an ideal choice and their colour can look good in a Mediterranean garden scheme or courtyard garden, where these flowers will look at home. Compost For Ranunculus These ranunculi will grow best in a medium made up of one part loam, one part leaf mould, and one part grit. You can also use any peat-free, loam-based multipurpose compost with a grit added at a ratio of two parts compost mix by one part horticultural grit. Potting Up Ranunculus Ranunculus are grown from tubers or from seed. Young plants can also often be purchased from garden centres or plant nurseries. There are larger tubers that will provide more flowers and smaller tubers that will not produce as many. The tubers should be planted with the pointed ends (finger-like protuberances) pointing down and should be set around 5cm deep. Water well upon planting, but then hold off watering again until you see sprouts so that the tubers do not rot. It is also a good idea to hydrate the claw-like tubers by soaking them for a few hours before planting. How Many Plants Per Pot? How many you can plant per pot will depend on which specific variety you are growing, and on the size of the container. As a general rule of thumb, the tubers should be planted 30cm apart if they are larger ones, and around 10cm apart if they are smaller ones. You could place 3-4 smaller plants into a 25-30cm pot. Container Ranunculus Care Place containers in a sunny and sheltered spot outdoors, or under cover in an unheated greenhouse or polytunnel, ensuring good light levels and ventilation. “If you’ve got an open porch which receives sun for a good portion of the day, I can hardly think of a better plant for late spring impact,” shares Peter Lickorish, a Horticultural Consultant. “If there’s one thing these plants hate, it’s sitting wet. “A porch provides the rain shadow and shelter that these plants appreciate, whilst giving them the light they crave, unless north-facing.” Water your ranunculi in pots whenever the top few centimetres of soil is dry to the touch, but make sure that excess water can always drain away freely and never allow waterlogged conditions to develop. Add a mulch around the top of the container to retain moisture, ensuring that this does not touch the plants themselves and that the base of the stems remains free and clear or they may rot and develop fungal issues. A grit mulch can be decorative and suppress pot weeds too. Add a balanced organic fertiliser on planting and feed with an organic, potash-rich organic liquid feed every couple of weeks during the blooming period for best results. Deadhead ranunculus regularly to encourage the plants to focus on flowers rather than seed production (unless you want to harvest seed to sow). The plants should be left with their foliage intact after flowering. Protect from early frosts with horticultural fleece or other protective measures if growing outdoors. After the foliage turns yellow and dries up, store the plant in a cool but frost-free location. “For seasonal containers, you can lift and pot tubers into 1 litre pots after flowering, for storing over late summer, autumn and winter, when they are dormant,” adds Peter. Cease watering and then resume watering only once new growth emerges once more. You can also lift and store the tubers in a dry, cool location to replant in spring. These are not the easiest plants to cultivate, but many feel that the beauty of the flowers and their relative longevity when cut makes the effort worthwhile.
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They Do Better In The Ground, But Hellebores Can Also Be Grown In Pots Long Term
IN THIS GUIDE Should You Grow Hellebore In Pots? Suitable Pots For Hellebore Suitable Compost Potting Up Hellebore Potted Hellebore Care Hellebores are often excellent choices to bring colour and flowers for pollinators to your garden in winter and late spring. They also often have impressive foliage which can be just as attractive as the flowers. Typically plants suited to woodland edges and part-shaded borders, hellebores can work in a wide range of different gardens, in a wide range of settings. There are many interesting types and cultivars to choose from. Should You Grow Hellebore In Pots? Hellebores can be grown in containers. They can make good choices for a container garden outdoors and some, like the Christmas rose, can also be grown as houseplants for decoration over the winter months. However, some may keep hellebores like Christmas roses in containers indoors temporarily, then simply toss them out come spring. This is very wasteful as with the right care, you can keep these perennial plants growing in containers longer term. However, most hellebores do best in the ground longer term, so where possible, it is best to use them for winter displays before transplanting them into the garden. “I have grown Hellebores in pots mainly as potted-up seedlings of those in the ground,” shares Master Horticulturist Colin Skelly. “I have not used them as display plants, but if potted on into larger terracottas, this would be an opportunity to utilise these young plants before they get planted into the ground.” Hellebores which are more tender can be grown permanently in containers, so they can be moved indoors or under cover when colder weather arrives. Suitable Pots For Hellebore When choosing a container for hellebores, remember that they do not like to be transplanted, so disruption should be kept to a minimum. Choose a large container that your plant will be comfortable in over a long period of time to avoid later disturbance. The depth of the pot is important because of the root growth pattern of these plants, which mostly grow down. Make sure that you choose a pot which has good drainage at the base, since while hellebores like a rich and moist medium, they cannot cope with soggy or waterlogged conditions. Suitable Compost The container that you choose for your hellebore should be filled with peat-free compost or potting soil which is rich in organic matter. Potting Up Hellebore Hellebores can be potted up into containers at any time of the year. Often, they are purchased as pot-grown specimens while they are in flower and can be carefully transferred to the pot in which you will grow them longer term. Plant hellebores to the same level that they were at in their previous pot. Think carefully before placing them as, once planted, they hate to be moved. Get it right the first time and let the hellebore settle into its more permanent position. Companion Planting Remember, when potting up Christmas Rose plants, that they do not necessarily have to be grown in containers on their own. One of the great things about hellebores is that they can often work well in mixed container displays for the winter container garden. Hellebore and heathers They can look lovely alongside heathers, sedges, and a range of early spring bulbs like cyclamen, crocuses, or alongside winter bedding plants. Potted Hellebore Care Place containers in full sun to partial shade, depending on the type and cultivar you have chosen. After potting up, mulch around your hellebore with compost or other organic matter, but take care not to pile the mulch around the base of the stems, as this can cause rotting. Water well, especially during establishment. Keep the medium moist but take care not to create waterlogged conditions and make sure excess water can drain away freely. Feed regularly with a balanced, organic liquid plant feed when growing in pots, and replenish mulch annually in spring to maintain fertility. Encourage flowering with a potassium-rich organic liquid plant feed. Some hellebores need special winter care to protect them from cold and wet weather, and some should be moved to a more sheltered spot or undercover for winter. With oriental hybrids, cut back old leaves in late winter or early spring to show off the flowers to best effect and control disease. With other types, remove any damaged or diseased foliage in autumn.
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Calibrachoa ‘Million Bells’ - Are They Worth It For One Season Of Growth?
IN THIS GUIDE Overview Reasons To Avoid Planting How To Grow Planting Ongoing Plant Care References Calibrachoa is a popular half-hardy bedding plant for a summer container garden. Its pretty bell-shaped flowers look like mini petunias and come in a wide range of colours. Overview Botanical Name Calibrachoa Common Name(s) Million Bells Plant Type Evergreen Perennial Native Area South & Central America Hardiness Rating H2 Foliage Evergreen Flowers Petunia-like, 2-3cm in diameter in a range of hues When To Plant May-June Calibrachoas, you might be surprised to learn, are actually in the same plant family as potatoes, tomatoes and peppers (Solanaceae).1 They are, in their native South American range, short-lived perennials or subshrubs, but they are treated as annuals in the UK and other temperate climate gardens.2 The Million Bells series is a collection of hybrid calibrachoa commonly cultivated as garden plants. Most frequently, they are used as summer bedding plants in hanging baskets or pots, as they have a trailing habit. They typically provide an excellent flowering display between early summer to early autumn, before temperatures fall and the plants are simply added to your composting system. Reasons To Avoid Planting For sustainable, eco-friendly gardeners like me, plants like this one are somewhat problematic. While many love these pretty flowers and the way in which they trail over the edges of containers and hanging baskets, they pose a problem for those who want to garden in a more ethical way. The problem is that these are hybrids, which cannot be grown from seed, and you cannot propagate these plants yourself at home because most are trademarked and it is technically illegal.3 Plug plants or pot-grown plants are available relatively inexpensively from garden centres, but most if not all come in plastic pots, and most come in peat-based compost – things we should all be trying to avoid. I personally would not purchase these because I don’t think the true cost (to people and planet) is worth it for just one season of growth. I would always try to go for options which I can grow from seed, or propagate myself for future years – but of course, this is a personal choice. How To Grow As mentioned above, Calibrachoa hybrids cannot be grown from seed. If you wish to grow these plants then you must either pick up plug plants in the early spring or somewhat larger plants in late spring or early summer. Planting Plant out calibrachoa once all risk of frost has well and truly passed in your area. These are tender plants which cannot cope with temperatures below 1-5°C. Plug plants are the most affordable option, but remember that plug plants purchased in early spring must be potted up and grown in a frost-free environment before they are hardened off and planted out from late May. You will need to make sure you have a suitable spot in which to do this. Ongoing Plant Care Million bells may look great, but it is important to understand that though this series is bred to be better for UK growing, and can cope with poor summer weather, it is still quite fussy about exactly how and where it will grow and does require some conscientious care. Aspect Million Bells must be positioned in a sheltered spot in full sun. A hanging basket or container against a sunny, south-facing wall is ideal. Soil Requirements These plants can be planted in any multipurpose, peat-free compost, or in any free-draining yet moist growing medium or soil. You can grow these in a bed or border, but they are typically grown in containers or hanging baskets because they look good trailing over the sides. Note that the containers that you choose should be moderately good at retaining moisture, but must allow excess water to drain away freely. Make sure there are good drainage holes and use pot feet to raise containers up off the ground. Watering Calibrachoa should be watered regularly over the summer months. Although these plants will not tolerate waterlogged conditions, they will also suffer if allowed to dry out. Keep the growing medium moist and remember that this could involve watering every day, perhaps even more often if the weather is very warm and dry. Fertilising Feed these plants every couple of weeks from mid-summer with a high-potassium organic liquid plant feed like comfrey tea or seaweed extract. Pruning No deadheading is required as these plants drop their spent flowers on their own, but you may wish to pinch back each stem, nipping off the growing tip, as this can prevent legginess and encourage the plants to bush out and produce more flowers. Overwintering These are single-season plants which are only used for summer bedding and are composted once the weather turns in autumn. Propagating As mentioned above, while Million bells could technically be propagated by means of softwood cuttings, this is technically illegal since the plants are trademarked. New plants must be purchased each year if you want to continue to grow these flowers in your garden in successive years. Common Issues Calibrachoas can be rather fussy plants when it comes to temperature, sunlight and water. They will not flower well if they are grown in an area with too much shade and will die in cold temperatures and can wilt when the temperatures are very high. Flowering will also be poor if you have not watered consistently, and wilting can be due to a lack of water or can be a sign of overwatering, which may have led to root rot. Grey mould is another common issue and can be a sign that you have overwatered. Yellowing leaves can be a sign of a nutrient deficiency and may mean that extra feeding is required. Calibrachoas can also be bothered by pests like aphids, slugs and snails, though these can usually be controlled organically by attracting ladybirds, hedgehogs, birds and other beneficial predatory wildlife to your garden. “In my experience, other organic methods, such as treating the compost in pots with nematodes and applying copper tape around the edge of pots, can be very effective at deterring slugs and snails,” says Roy Nicol, a Professional Horticulturist with over 10 years of experience. References 1. Calibrachoa x hybrida. (n.d.). North Carolina Extension Gardener Plant Toolbox. Retrieved March 13, 2023, from https://plants.ces.ncsu.edu/plants/calibrachoa-x-hybrida/ 2. Calibrachoa. (n.d.). Kew Royal Botanic Gardens. Retrieved March 13, 2023, from https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:38309-1 3. Get plant breeders’ rights for your new variety. (2023, January 5). GOV.UK. Retrieved March 13, 2023, from https://www.gov.uk/guidance/plant-breeders-rights
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Thin Stalks On Your Rhubarb? Your Plant Might Need Dividing Or Fertilising
IN THIS GUIDE 1) A Lack Of Nutrients 2) The Plant Is Immature 3) It Needs Dividing 4) Harvesting Incorrectly 5) Flowering & Going To Seed References Rhubarb is a perennial vegetable that is widely grown for its sweet and vibrant stems for culinary purposes. Part of the Polygonaceae family, rhubarb is thought to originate from Siberia and China, which is why it can sometimes struggle when grown in our very different climates.1 One of the most common issues gardeners can experience when growing rhubarb is the production of thin, rather than thick stalks, which can be caused by a number of factors: A lack of nutrients from the soil. If the plant is young or immature. Older plants that need to be divided. From being harvested incorrectly. The stems flowering and going to stem. We explain each of these reasons with solutions down below. 1) A Lack Of Nutrients Rhubarb plants are hungry feeders, so if they are not given the correct nutrients they may fail to thrive – and ultimately produce thin stalks. In autumn or early spring, a general-purpose fertiliser or mulch of well-rotted manure or organic matter can be applied thickly around the crown of the plant, which will give it a boost for the growing season ahead. Rhubarb prefers moist, but free-draining soil and will struggle if grown in compacted soil prone to waterlogging. 2) The Plant Is Immature Newly planted rhubarb may produce weak and thin growth early on and should not be harvested until they are suitably established and able to handle being picked from. To encourage a strong and vigorous plant for many years to come, it is advisable to leave new plants or divisions to settle and bulk up for at least 2 years before taking a harvest. 3) It Needs Dividing Rhubarb plants are generally tough and can live in excess of 10 years. However, over time they may become congested and produce weak stems, which is an indication that they should be divided. It is generally recommended that rhubarb plants are divided every 4-5 years to replace older specimens and maintain plant health. 4) Harvesting Incorrectly When rhubarb stalks are harvested can also have a bearing on the stem thickness and size, as over-harvesting can weaken the plant and subsequent crop. Harvesting stems from established plants can generally be performed from early spring until early summer. Although it might be tempting, cropping after June should be avoided to encourage a healthy harvest in the following years. 5) Flowering & Going To Seed Although unusual, rhubarb plants can produce flowering stalks during the summer months which need to be swiftly removed. These flowering stems, if given time, will go to seed and use up the plant’s precious energy, causing it to weaken and potentially produce a poor future harvest. To remove the flowers, simply cut the flowering stems at the base with a clean and sharp knife. References 1. Rhubarb (Rheum species): the role of Edinburgh in its cultivation and development. (2017). Retrieved March 23, 2023, from https://www.rcpe.ac.uk/sites/default/files/jrcpe_47_1_lee.pdf
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'Get The Balance Right With Rhubarb' - Dan Ori On Yellowing Leaves And Their Causes
IN THIS GUIDE Nutrient Deficiencies Waterlogged Soil Temperature Watering Rhubarb is a hardy perennial vegetable that is commonly grown for its delicious and vibrant stems. However, even though it is generally easy to grow and care for, gardeners can face some challenges when growing it as it is not native to the UK. One of the most common problems gardeners can experience when growing rhubarb is yellow leaves. This article will consider the possible causes of why rhubarb leaves turn yellow, what can be done to prevent this and any remedial action that can be taken. Nutrient Deficiencies Rhubarb plants are hungry feeders and yellowing leaves can sometimes suggest a lack of nutrients and minerals in the soil necessary for it to thrive. A thick annual mulch of organic matter or well-rotted manure applied in early spring is highly recommended, especially when growing rhubarb on poor soils, as well as an application of a general-purpose fertiliser. However, it is important to note that when applying a layer of mulch, you need to be careful not to cover the crown of the plant, as this can lead to crown rot and more serious issues. Waterlogged Soil Rhubarb grows best on moist but free-draining soil and will struggle if grown on a compacted site or an area that is prone to waterlogged soil, which can potentially lead to foliage yellowing. “The trick is to get the balance right with Rhubarb,” says Horticulturist Dan Ori. “It needs moist soil to crop well but it doesn’t do well in waterlogged soil, as the crown will often rot.” If your garden has compacted soil, it can be made workable and suitable for growing rhubarb by digging it over and adding organic matter such as homemade compost or well-rotted manure. It is worth noting that rhubarb can also grow well in a large pot or container as not only can the growing medium be mixed to suit the plant, but it can be moved into the best spot for it to grow. With regards to the aspect of where to grow rhubarb, it prefers a sheltered and south-facing site that will receive full sun. Rhubarb can be grown in partial shade, although may struggle if it does not receive enough direct light. Temperature Rhubarb is a hardy plant with a rating of H5, indicating that it can withstand winter temperatures down to as low as -10-15°C. Rhubarb originates from colder climates and actually requires a cold period of temperatures around 0°C for a couple of months in order to produce healthy foliage and stems the following season. Although low enough winter temperatures are unlikely to be a problem for most parts of the UK, it is worth noting that this may be an issue for much milder and coastal regions. Watering Yellowing leaves and wilting can often be an early sign of either over or under-watering rhubarb. Rhubarb requires moist but not overly wet soil and thorough watering of the roots during hot and dry spells is advised, as underwatering can lead to reduced and even a complete halt of all growth. However, overwatering can also be harmful as it can lead to crown rot and waterlogged soil. As a general rule, it is recommended to allow the top 2-4cm of soil to dry out before watering again and to avoid watering if the soil is already damp.
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