Growing
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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Grow Ipomoea Alba ‘Moonflower Vine’ For Breathtaking Flowers In The Evening
IN THIS GUIDE Overview Growing From Seed Ipomoea Alba Care Light Temperature & Humidity Preferred Soil & Drainage Watering Feeding Pruning Common Issues References There are two plants that go by the name moonflower, so let’s make sure you’re reading about the right one. The Ipomoea alba is a wild-growing vine and can grow to enormous heights. Its flowers open at dusk, bloom in the night, and then die in the morning to be replaced again the next afternoon. The other plant, Datura innoxia, grows to a smaller height and its flowers don’t die each day. In this article, we will be focusing on the first: the moonflower vine. Overview Botanical Name Ipomoea alba Common Name(s) Moonflower / belle de nuit Plant Type Annual Climber Native Area North & South America and the Caribbean Hardiness Rating H5 Foliage Evergreen Flowers Coiled white petals that unfurl to reveal white circular shape When To Plant All year round (when cultivated indoors) When To Prune September-February One of the joys of gardening is selecting flowers that work well together in terms of colour, bloom time, and other factors to create lasting variety and visual interest. You can liven up a medley of colour by putting it against a backdrop of white, for example; or pick a few plants that flower in winter to extend your season interest. You can also look for plants that flower at different times of day, with the moonflower vine, I. alba, being a fine example of a flower whose bloom is most breathtaking in the evening and through the night. This plant makes a great addition to gardens that play host to evening gatherings, whether they be barbecues or bonfires. As a native to more tropical climes, the moonflower vine does grow best in warm temperatures, but British gardeners are able to get good results by growing it as an annual. “Ipomoea alba is a perennial in its native tropical Americas but a warm season annual in the UK (it dies off because of winter cold not because of its life cycle),” says Horticultural Consultant Colin Skelly. “I love trying to grow plants from warmer regions in the UK. In a long, hot summer you can get great results. “It can be challenging if the summer is unsettled by colder and wetter weather but that makes the joy when it comes off even more euphoric!” Growing From Seed Growing moonflower vines from seed is possible, and in British conditions, it’s recommended you plant them between 6-8 weeks ahead of outdoor planting. You can plant outdoors when temperatures are consistently over 15°C, so aim to sow in late March to early April to plant in late May or early June. Scratch the exterior of the seed with a knife or sandpaper, taking care to not damage the inside. Soak the seed for a couple of hours in warm water. Once the seed swells, plant it between 5-7mm below the surface of moist but well-drained seed compost. To propagate, these seeds need temperatures between 20-25°C. It can take anywhere from 5-45 days for propagation, although the lower end of this range is most likely. Move to a pot once the seedlings are established and make sure it’s big enough to accommodate their growth. If you’re growing outside, wait until the last frost has passed and remember what we said about temperatures being consistently over 15°C. Alternatively you can grow in a conservatory or greenhouse. Is It Invasive? This plant is considered invasive in some more tropical regions. In the UK it can be borderline invasive, so make sure to keep an eye on how far your plant is spreading. Ipomoea Alba Care Once your moonflower is established, it’s a fairly undemanding plant. It’s always good to know how to keep your plants in tip-top condition though, so here are some Ipomoea alba care guidelines to help you out. Light It’ll be happy growing in full sun or partial shade, but as a general rule more sun increases the number of blooms you’ll get from a mature moonflower. Temperature & Humidity Being native to warmer regions of North America, South America and the Caribbean, this plant is built to thrive in higher temperatures.1 Growers in warm climates will be treated to a perennial growth habit, whereas British gardeners are most likely to have an annual moonflower. An outdoor temperature above 15°C is most conducive to a healthy plant. Preferred Soil & Drainage Go for moist, well-drained soil for best results. Chalk, sand or loam soils should be suitable for a moonflower, with seed compost for germination. Watering Water regularly when plants are young and keep your moonflower hydrated as it grows. This plant can grow to impressive heights and so requires plenty of water to satiate its thirst! Feeding A high phosphorus fertiliser will correlate with a more luscious floral bloom, whereas high nitrogen fertiliser may reduce the number of flowers – instead stimulating the growth of more foliage. Check the instructions for the fertiliser to see whether it needs diluting. Pruning As an annual, you can prune this plant back after the flowering season to give space for next year’s plant to grow. Bear in mind, however, that I. alba puts forth attractive and intriguing seed pods after flowering, and some gardeners decide to keep these plants around a little longer so they can enjoy these seeds. As an enthusiastic grower, you may find yourself wanting to trim back your moonflower vine throughout its flowering season to keep it looking tidy and organised. This is fine, just be careful not to prune back too aggressively. Common Issues Moonflowers aren’t known to be particularly prone to any diseases, meaning they should give you a fairly low amount of hassle. There are a few insects to keep an eye out for, however, including aphids, spider mites and leaf beetles. Here’s how to reduce the risk of an infestation: Be vigilant: inspect the leaves of your moonflower vine every once in a while to make sure there are no insects visible, or any telltale signs of their presence (eg. holes in leaves, residue on their underside, or even eggs). Keep an eye on surrounding plants: pests are liable to make the jump between plants that live close together, so if a neighbouring plant is playing host to some pests, be extra vigilant. Remove infected areas if they are small. Removing insects by hand is sometimes enough to nip things in the bud. Just take care to check back regularly. Introduce predatory species, as bringing ladybirds or other insects into your garden can sometimes keep infestations at bay. Consider insecticides: if none of these options are working you may think about using insecticide products to kill the imposters, but just check the ingredients. Not all gardeners are thrilled about strong chemicals being used in their gardens! References 1. Rojas-Sandoval, J. (2022). Ipomoea alba (white moonflower ). CABI Compendium, CABI Compendium. https://doi.org/10.1079/cabicompendium.119823
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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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Honey Fungus Can Target The Roots Of Woody Plants - Here's How To Manage An Outbreak
IN THIS GUIDE What Is Honey Fungus? Identifying Honey Fungus Causes & How It Spreads Which Plants Are Most At Risk? How To Manage An Outbreak Honey Fungus Treatment Resistant Trees & Shrubs FAQs References Honey fungus is a serious fungal disease that has the capacity to destroy certain shrubs, trees and perennial plants in the garden. Unfortunately, honey fungus can be a severe problem if identified in the garden and can lead to the loss of multiple specimens, as limited controls are available. However, if found to be present, prompt action can help to prevent its potential spread. What Is Honey Fungus? Honey fungus encompasses several species of Armillaria fungus that target and kill the roots of many woody plants and is considered to be a factor in oak decline, a disease affecting oak trees.1 The fungus can produce honey-coloured toadstools in late summer or early autumn, giving the fungus its common name. Armillaria mellea and A. gallica are the most common honey fungus species to be found present in gardens here in the United Kingdom.2 A parasitic fungus, armillaria can attack both broadleaf and coniferous shrubs and trees, along with some herbaceous perennials. Sadly, widespread here in the UK, it is also present in parts of Europe and North America. Identifying Honey Fungus Honey fungus can be hard to identify as it spreads under the soil surface and does not always produce the honey-coloured toadstools that are visible above ground. The clumps of honey-coloured toadstools appear from the end of summer onwards. However, these mushrooms tend not to appear until the disease is already well established and shrubs and trees are badly infected. The toadstools tend to grow in clumps on living and dead wood. The mushroom caps are brown on top with white gills underneath, which turn brown over time and can develop a wavy edge as they mature. A white collar is present on the stems underneath the gills. Reaching a height of 10-15cm their stems can grow to 1.5cm in diameter. Other tell-tale signs that honey fungus is present, is the display of rhizomorphs or ‘black bootlaces’ in the soil around the plant or under the bark, along with white growths called mycelium, which grow between the bark and the wood underneath.3 “The most reliable way to identify honey fungus is by peeling back the bark at the base of the tree or shrub where the white mycelium will be evident, along with a strong smell of mushrooms,” shares Master Horticulturist Roy Nicol. “Rhizomorphs often can’t be seen, but the best chance to spot them is where they are attached to the root at the base of the plant.” However, often the first signs of honey fungus aren’t the toadstools or bootlaces, but reduced plant vigour, dieback of growth, loss of flowers, pale foliage and cracking and bleeding at the base of the tree. These can all easily be mistaken as symptoms of other diseases or problems other than honey fungus. Causes & How It Spreads In the wild, honey fungus is rarely an issue as other fungi growing in the area limit its growth. However, in cultivated gardens where fungi are often discouraged, honey fungus can take over as other species are not present to keep it in check. Honey fungus mainly spreads underground by way of the rhizomorphs under the soil as well as from infected roots transmitting the disease to other plants’ root systems nearby.4 The fungi can also produce spores and the latest research indicates some species such as A. mellea may spread by spore dispersal and then via the underground rhizomorphs.5 The rhizomorphs travel under the soil at a depth of 15-45cm and at a frightening pace of up to 1m a year until plants up to 30m away are attacked. This speed, along with the fact that it is often unnoticeable until too late, is why honey fungus can affect large parts of a garden in a relatively short time. Which Plants Are Most At Risk? Regrettably, no plants are totally resistant to succumbing to honey fungus, however, it does seem to target some plants a lot more readily than others. The Royal Horticultural Society (RHS) now provides an updated list of plants more susceptible to honey fungus.6 Common garden plants which are highly susceptible to the disease include Lilac, Viburnum, Cotoneaster, Weigela, privet, Photinia, Forsythia, Buddleja, Ceonothus and Acers. “A common cause of honey fungus spread I have found in gardens are where susceptible trees, such as Oak, Willow, Horsechestnut, Birch, Cedar, Walnut and Leyland Cypress, are infected and then cut down,” shares Peter. “The fungus then spreads to garden plants looking for new sources of material to consume.” How To Manage An Outbreak Not to scare, but the largest area of honey fungus discovered so far is in a forest in Oregon, USA and covers an area of approximately 965 hectares.7 However, this infected area is thought to be thousands of years old and has had a lot of time to grow and spread. Honey fungus is not a notifiable disease – nevertheless, if an outbreak is identified, it is advisable to take swift action to minimise the possible damage. Noting which shrubs and trees and their locations around the garden have previously been, or currently are infected, can be helpful in working out which areas the fungus is present and demand focussed treatment. Strategies to manage an outbreak can include maintaining good plant health, limiting the spread of the disease and removing any sources of the fungus. Since honey fungus can be so difficult to eradicate, a combination of all these strategies is often advocated. Honey Fungus Treatment Removal of Affected Material Treatment for honey fungus is unfortunately limited, as there are no chemicals or fungicides currently approved to treat the disease. The only surefire way of eradicating the fungi is by completely removing and destroying the affected material, as labour-intensive and destructive as this may be. When removing an infected shrub or tree, its entirety must be gotten rid of including the stump and infected root system, as, without any infected material to feed off, the honey fungus rhizomorphs will die. Honey fungus has been known to continue growing on infected wood even after felling. Therefore, it is recommended to either dispose of all the infected material either at a managed landfill site or through burning. Reduce Honey Fungus Spreading Stopping the spread of the honey fungus is a key part of any treatment and keeping the rest of the garden disease free. This can be achieved by installing a tough plastic sheet barrier, such as a butyl liner, to a depth of 50cm around the infected area and by removing the adjacent plants, even if healthy. If part of a hedge is infected with the honey fungus it is recommended to remove at least one healthy plant on either side of the infected specimens to prevent any further spread. The disease can also be reduced by cultivating the area and leaving the affected site fallow for at least one year, which will allow the removal of any bootlaces and any existing fungus to die off from lack of a host to feed off. If the idea of leaving the treated area, which can be large, fallow and bare for a long time is too much, then the site can be covered with a woven weed membrane and hidden by a layer of gravel, interspersed with planted-up containers. Grassing over the treated area can also be an option. However, even though this can be considered a more aesthetic option, it is not considered to be as effective as leaving the site bare. Promoting Plant Health Promoting plant health is also key in the prevention of honey fungus disease. Healthy plants which are pruned correctly and watered and fed as necessary will be able to potentially resist the disease better than those which are neglected. Ensuring that any shrubs and trees within the vicinity of the disease are planted at their correct depth will also help prevent them from succumbing to honey fungus, as if planted too deeply, they are more susceptible. Resistant Trees & Shrubs Once the site has been cleared and left fallow for the appropriate length of time, replanting with resistant specimens is strongly advised in case any of the fungi or disease is still left in the soil. The RHS recommends replanting with species that are rarely affected by honey fungus, which includes lavender, yew, pittosporum, acacia, cotinus, hydrangea, philadelphus, salvia and pear trees.8 FAQs Does Honey Fungus Always Spread? Unfortunately, honey fungus does not only always spread, but it can spread at a distance of 1m per year and infect nearby shrubs and trees with alarming speed. How Long Does Honey Fungus Stay In The Soil? Being parasitic, honey fungus can exist for many years if it has material to live off. However, if all of the infected trees and shrubs are removed, along with all their roots, then one year is the suggested time frame to wait before replanting the area. As a test, a few strawberry plants can be planted in the treated area before replanting, which if the disease is still present, will die within weeks and indicate that the site must be left for longer. Should You Remove Fungus From A Tree? Removing honey fungus toadstools alone from a tree or shrub is not recommended as the disease is most present in the plant, its roots and under the ground. It is advisable to remove all of the fungi, shrubs, trees and roots at the same time and dispose of them judiciously. Does Jeyes Fluid Kill Honey Fungus? In the past, Jeyes Fluid or Armillatox has sometimes been used for the purpose of trying to sterilise the soil surrounding any infected trees or shrubs with honey fungus. However, using these products for this use has since been banned (see the list of RHS Withdrawn Chemicals for more insight). There is no chemical control currently approved. References 1. Armillaria – honey fungus. (2022, February 9). Forest Research. Retrieved March 17, 2023, from https://www.forestresearch.gov.uk/tools-and-resources/fthr/pest-and-disease-resources/chronic-oak-decline-dieback/biotic-and-abiotic-factors-which-contribute-to-oak-decline/armillaria-honey-fungus/ 2. Incidence of Armillaria species in U.K. gardens. (2017, July). ResearchGate. Retrieved March 17, 2023, from https://www.researchgate.net/figure/Incidence-of-Armillaria-species-in-UK-gardens-A-A-gallica-B-A-mellea-and-C-A_fig2_318250914 3. Honey Fungus. (n.d.). NatureSpot. Retrieved March 17, 2023, from https://www.naturespot.org.uk/species/honey-fungus 4. Wingfield, M. (2004). Armillaria. Science Direct, 816–822. https://doi.org/10.1016/b0-12-145160-7/00062-4 5. Armillaria. (n.d.). ScienceDirect Topics. Retrieved June 19, 2023, from https://doi.org/10.1016/B978-0-323-85042-1.00004-5 6. Honey fungus plant list. (n.d.). Royal Horticultural Society. Retrieved March 17, 2023, from https://www.rhs.org.uk/advice/pdfs/honey-fungus-host-list.pdf 7. Casselman, A. (2007, October 4). Strange but True: The Largest Organism on Earth Is a Fungus. Scientific American. Retrieved March 17, 2023, from https://www.scientificamerican.com/article/strange-but-true-largest-organism-is-fungus/ 8. Honey fungus. (n.d.). Royal Horticultural Society. Retrieved March 17, 2023, from https://www.rhs.org.uk/disease/honey-fungus
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16 Radiant Wallflower Types Including Bowles’s Mauve, The Most Popular Cultivar
IN THIS GUIDE 1) E. cheiri (Aegean Wallflower) 2) E. ‘Bowles’s Mauve’ 3) E. ‘Ivory White’ 4) E. scoparium 5) E. menziesii 6) E. ‘Golden Jubilee’ 7) E. capitatum 8) E. pallasii 9) E. baeticum & E. cazorlense 10) E. ‘Night Skies’ 11) E. ‘Red Jep’ 12) E. ‘Blood Red’ 13) E. ‘Constant Cheer’ 14) E. linifolium ‘Variegatum’ 15) E. ‘Fair Lady’ 16) E. ‘Persian Carpet’ References Erysimum species, hybrids, and cultivars are widely used in public parks and formal gardens. They are used as companion plants, as bed displays, to create blocks of colours, and to make patterns. As for those garden paintings of clocks and heraldry symbols that one sees, Wallflowers are a common component. All said, there are over 270 generally-accepted species and that does not include cultivars!1 In height, these plants range from as high as 80cm, e.g. Bowles’s Mauve, down to about 22cm which is the size of some dwarf species native to the Alps. It is hardly possible to do justice to such an interesting and diverse genus in a single article but here is a solid sixteen of my absolute favourites of this sweet-scented plant. In our quick tour of Erysimum species we must start with E. cheiri and E. ‘Bowles’s Mauve’: E. cheiri is the ‘original’ species from which most British varieties descend and Bowles’s Mauve is probably the most popular cultivar. 1) E. cheiri (Aegean Wallflower) Native to the Mediterranean region but is now a common sight in the UK. “The wallflower is a good example of an archaeophyte, a plant that has become naturalised outside of its native range before the modern period (modern introductions are known as neophytes),” says Colin Skelly, an RHS verified Master Horticulturist. “In the UK, introductions prior to the end of the 15th century are regarded as archaeophytes. “It is thought that they may have come across castle-building Normans. When you grow wallflowers you are part of the long history of the travels and cultivation of this versatile species.” Though a perennial, it is treated as a biennial. This fairly tall species bears spikes of scented flowers in clusters. Their colour varies from a merry golden-yellow to deep orange. 2) E. ‘Bowles’s Mauve’ Flowers from early Spring through mid-Autumn which is one of the reasons it is valued. The petals are delicate and slightly wrinkly. The colour varies from a pale lilac to a solid mauve. The greyish-green lanceolate to linear leaves provide attractive and virtually evergreen foliage. 3) E. ‘Ivory White’ A cultivar of E. cheiri. The plants are small and bushy, while the rich, creamy ivory white shade of the flower is a soothing tonic for human eyes and the flower itself is a literal tonic for bees which make a ‘beeline’ for these blooms. These plants are ideal for edging and bordering. 4) E. scoparium A species native to the montane areas of the Canary Islands. It is an erect shrub with very attractive flowers in shades of lilac and pale purple. However, the distinctive feature about this species is that both the leaves and the petals are a perfect match for each other, being very narrow; among the narrowest in this genus. 5) E. menziesii If you can find it! It is a rare and endangered species found in a dwindling location in California. Its foliage is as unusual as the plant; the leaves are very dark and satiny. The floral petals are distinctively shaped, being rounded and slightly convex, and are of a buttercup hue. 6) E. ‘Golden Jubilee’ One of the more popular cultivars and if you can’t find E. menziesii, you can use this one as a sub because the flowers are somewhat similar both in shape and in hue. Where it varies is that this is a clumping, robust species that you’ll have no trouble finding and maintaining. 7) E. capitatum These species are relatively tall for Erysimum. While E. asperum is native to the American Mid-West in the wide open prairies, related species E. capitatum is found further north in the North-West and Canada. The flowers are borne on longish, stiff stalks. Their petals are wide open almost in a single plane, giving the flower an innocent, frank look. Their hues, ranging from bright and deep yellow to a mellow orange, add to their appeal. 8) E. pallasii One of the hardiest species for it is native to Russia’s northernmost regions, Greenland, and North-Western Canada. It has a woody stem and oblong leaves. The flowers are petite and have eye-catching mauve to deep purple hues that are very striking against the plant’s foliage. 9) E. baeticum & E. cazorlense These flowers have virtually the same hue as those of pallasii but the resemblance ends there. The petals are narrower and more separated; as for the plants, they are endemic to sunny Spain! They are profuse bloomers; however, the linear leaves are also points of interest as they are nearly as long and narrow as grass blades. 10) E. ‘Night Skies’ A profuse bloomer that can flower until autumn. The waft of their sweet scent will attract bees to your garden. The full petals partially overlap in a whorl. As for the colour, its gentle, soothing tones vary from a perfect baby pink through lilac. 11) E. ‘Red Jep’ A popular perennial. Bushy, verdant lanceolate foliage sets off the flower perfectly, which features very full, imbricated petals that are typically of a purplish-scarlet tone but can vary from red to purple. Their fragrance draws bees and it grows to about 30cm. 12) E. ‘Blood Red’ Twice as tall as E. ‘Red Jep’, reaching a height of 60cm; what’s more, it’s hue is probably ten times as intense. The full petals are wide open and valvate. No cultivar can be more aptly named, for while the hue is in various tones of deep red and crimson, you will often find it in a perfect ‘blood red’. This one’s not for the faint of heart! 13) E. ‘Constant Cheer’ A very popular variety and is so named because it blooms ‘constantly’ through spring and summer. It is a small evergreen perennial with grey-green lance-like leaves. Their flowers spread ‘cheer’ through their happy tones of orange, pink, mauve, and purple. 14) E. linifolium ‘Variegatum’ One of the unusual Wallflower varieties that takes its name from its ‘variegated’ foliage. The lanceolate leaves of this perennial are bicoloured; they have a distinct, fairly thick, border of cream-yellow enclosing a mid-tone green. The intense mauve-to-puple flowers are both striking and very fragrant, doubling – or trebling – this hybrid’s charms. 15) E. ‘Fair Lady’ Could just as well be called ‘Variegatum’ because of its flowers. Yet that would be an understatement. This petite sub-shrub’s flowers simply dazzle. Their pallete is remarkable, ranging from pastel creams and pinks to brilliant vermilion and hot purple. Best of all, frequently the floral petals themselves are variegated, occurring in tones of cream, yellow, pink, and orange. 16) E. ‘Persian Carpet’ Another variety with multi-coloured and even ‘variegated’ flowers, but this one’s a dwarf variety. The scented flowers have broad rounded petals and occur in hues of cream and yellow through vermilion and scarlet and even purple. Sometimes, petals are bi-toned, have streaks, or are clearly gradated, adding to their visual appeal. References 1. Erysimum. (n.d.). Plants of the World Online. Retrieved May 22, 2023, from https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:329617-2#children
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27 Helianthemum 'Rock Rose' Varieties Including Endangered Ones At Risk Of Extinction
IN THIS GUIDE 1) H. apenninum 2) H. nummularium 3) H. ‘David’ 4) H. ‘The Bride’ 5) H. ‘Wisley Primrose’ 6) H. ‘Jubilee’ 7) H. ‘Ben Attow’ 8) H. ‘Praecox’ 9) H. ‘Marianne’ 10) H. ‘Orchard’s Medius Pink’ 11) H. ‘Rose Queen’ 12) H. ‘Rhodanthe Carneum’ 13) H. ‘Ben Lomond’ 14) H. ‘Georgeham’ 15) H. ‘Highdown Apricot’ 16) H. ‘Honeymoon’ 17) H. ‘Orchard’s Dwarf Orange’ 18) H. ‘Henfield Brilliant’ 19) H. ‘Ben Heckla’ 20) H. ‘Alice Howorth’ 21) H. ‘Orchard’s Griseo’ 22) H. ‘Dompfaff’ 23) H. ‘Orchard’s Pastel’ 24) H. ‘Cerise Queen’ 25) H. ‘Orchard’s Royale’ 26) H. ‘Fire Dragon’ 27) H. ‘Beech Park Red’ Endangered Varieties References Helianthemum has undergone significant floriculture in England with the result that a few double flowers have also been developed. One can choose from a total of 200-plus cultivars in a wide range of hues and tones spanning the entire warm spectrum plus white.1 Here are some of my favourite varieties to grow for beautiful low-growing shrubs: 1) H. apenninum Has linear to lanceolate leaves and produces snow-white flowers with a yellow central disk and stamens to match. This species can reach a height of 50cm. 2) H. nummularium The species from which the vast majority of cultivars have been developed. It attains a height of 30-40cm. It has oval leaves and bright yellow flowers with prominent orange stamens. The following selected cultivars typically bloom from late spring to the middle of summer: 3) H. ‘David’ Has lanceolate leaves and a pure white flower with sizeable central disks and visible buttery stamens. 4) H. ‘The Bride’ Has foliage that is distinctly silvery-green with a frosted appearance while the flowers are white or off-white with yellow eyes. This variety is a recipient of the RHS Award of Garden Merit. 5) H. ‘Wisley Primrose’ Has greyish-green lanceolate leaves and produces classic primrose yellow flowers with darker, buttery yellow centres. RHS Award of Garden Merit. 6) H. ‘Jubilee’ One of the few varieties to produce double flowers; these are of a primrose yellow hue. RHS Award of Garden Merit. 7) H. ‘Ben Attow’ This variety has dark green lanceolate leaves and produces lemon-yellow flowers with prominent matching stamens. 8) H. ‘Praecox’ has chalky-green lanceolate leaves and bears flowers that are fully yellow of a bright, sunny hue. 9) H. ‘Marianne’ has greyish-green pinnate leaves and bears whitish flowers that have a faint pink tinge or pink flush set off by bright yellow stamens. 10) H. ‘Orchard’s Medius Pink’ Has appealing light green leaves and bears baby pink flowers with sizeable central disks in orange which are further centred by bright yellow stamens. 11) H. ‘Rose Queen’ Has elliptic leaves of a greyish-green hue and bears soft pink flowers with golden eyes and prominent stamens. 12) H. ‘Rhodanthe Carneum’ Has silvery-grey elliptic leaves and bears soft pink flowers with yellow centres further accented by yellow stamens. RHS Award of Garden Merit. 13) H. ‘Ben Lomond’ Has dark green elliptic leaves and produces flowers of a classic baby pink hue that have prominent golden stamens. 14) H. ‘Georgeham’ Has greyish-green lanceolate leaves and bears bright pink flowers with a creamy pink disk further centred by prominent yellow stamens. 15) H. ‘Highdown Apricot’ Has greyish-green leaves with flowers of an unusual pastel apricot-pink hue with bright yellow central disks and visible yellow stamens. 16) H. ‘Honeymoon’ Has bright green elliptic leaves and produces peach to light orange flowers with prominent yellow stamens. 17) H. ‘Orchard’s Dwarf Orange’ Has light green elliptic leaves and bears flowers of a rich amber-orange with prominent yellow stamens. 18) H. ‘Henfield Brilliant’ Has lanceolate leaves of a frosted greyish-green hue and produces poppy orange flowers with visible yellow stamens. RHS Award of Garden Merit. 19) H. ‘Ben Heckla’ ‘Ben Heckla’ Has grey-green ovate leaves and bears rich orange flowers with large vermilion central disks with just-visible yellow stamens. 20) H. ‘Alice Howorth’ Has mid-green pinnate leaves and bears flowers that are of a chalky coral tone and red at the centres with prominent yellow stamens. 21) H. ‘Orchard’s Griseo’ Has bright green pinnate leaves and bears coral-pink flowers with very prominent buttery yellow stamens. 22) H. ‘Dompfaff’ Has dark green pinnate leaves and produces flowers of a chalky lipstick-red hue which are darker at the centres and have prominent yellow stamens. 23) H. ‘Orchard’s Pastel’ Has cool green lanceolate leaves and produces rose-red flowers with prominent yellow stamens. 24) H. ‘Cerise Queen’ One of the few varieties to produce double flowers; these are of a saturated pinkish-red or lipstick-red hue. 25) H. ‘Orchard’s Royale’ Has silvery-green lanceolate leaves and bears fuschia to magenta-toned flowers with bright yellow stamens. 26) H. ‘Fire Dragon’ Has bright green lanceolate leaves and bears scarlet flowers with a deeper red centre and visible yellow stamens. RHS Award of Garden Merit. 27) H. ‘Beech Park Red’ Has elliptic dark green leaves and produces bright red flowers with visible yellow stamens. Endangered Varieties The desirable varieties of Helianthemum are cultivated and grown in an increasing number of countries and are rising in popularity; indeed, eight of these little flowering shrubs have even been awarded the RHS’s Award of Garden Merit. “Many species with wild distributions will need the skills of gardeners to avoid extinction,” explains Master Horticulturist Colin Skelly. “Cultivated plants also face the threat of extinction as some cultivars fall out of fashion and are no longer grown.” But the realities could not be more different and more grim for the less well-known species – would you believe that some are on the road to extinction? H. songaricum & H. ordosicum Native to hilly regions of Southwestern China. Human settlements in their habitats and resultant habitat-altering activities, such as agriculture and grazing, have severely fragmented these species’ populations which have been declining for several years. This led to both species being categorised as ‘Endangered’ in the China Species Red List. H. marifolium & H. caput-felis These grow in the islands, cliffs, and coastal regions of the Western Mediterranean region. Their habitats have been disturbed and even taken over by tourist resorts and urban sprawl. H. marifolium is termed ‘Vulnerable’ and H. caput-felis ‘Rare’ and both are categorised as ‘Endangered’. Each species has been accorded a protected status under the respective country or region’s laws. No matter which varieties you choose to grow – the endangered ones or the AGM ones – these mat-forming evergreens that bear exceedingly pretty flowers over a long blooming season are truly no-care no-fuss plants that will bring their own unique charms to your garden. References 1. Roberts, A. (n.d.). Collection: Helianthemums . Helianthemums.co.uk. Retrieved March 16, 2023, from https://www.helianthemums.co.uk/collection/
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From Common Harebell To Milky Bellflower - Here's 15 Colourful Campanula
IN THIS GUIDE 1) C. portenschlagiana 2) C. rotundifolia 3) C. poscharskyana 4) C. lactiflora 5) C. pyramidalis 6) C. carpatica 7) C. glomerata 8) C. persicifolia 9) C. latifolia 10) C. sibirica 11) C. takesimana 12) C. garganica 13) C. medium 14) C. punctata 15) C. trachelium References Easy to grow and an absolute joy to behold, it’s no surprise that bellflowers, or campanulas, are a common sight in cottage gardens and border displays across the United Kingdom. Distributed across much of the Northern Hemisphere and often found in woodland areas, they’ll cope with most soil types and climates with ease, providing the terrain doesn’t become waterlogged. Despite the name, they come in many different shapes and colours, meaning there’s an option to suit all aesthetics. In fact, there are over 400 different types of campanulas to choose from.1 Listing all of them would be difficult, so I’ve whittled this list down to my favourite fifteen. All of the varieties on this list can be grown in full sun or partial shade and are unfussy with regard to exposed or sheltered conditions. 1) C. portenschlagiana COMMON NAME(S): Wall Bellflower / Adria Bellflower HARDINESS RATING: H5 FLOWERS: Purple FLOWERING SEASON(S): Summer Holder of an Award of Garden Merit from the RHS, this universally popular specimen is better known as the Dalmatian bellflower. The moniker is nothing to do with dogs, however, but rather with the region of Croatia from where it originates.2 With mat-forming tendencies and evergreen lush foliage, C. portenschlagiana bursts into life each summer with cascading lavender blossoms. Ideal for ground coverage in sunny borders. 2) C. rotundifolia COMMON NAME(S): Common Harebell / Scottish Bluebell HARDINESS RATING: H7 FLOWERS: Blue FLOWERING SEASON(S): Summer C. rotundifolia (colloquially known as the Scottish bluebell) is not precious about its growing conditions. It flourishes in particularly dry or nutrient-rich soils but can grow elsewhere too. Despite those humble beginnings, it’s still a bonnie sight to behold. Flowering from midsummer to early autumn, it produces dainty bell-shaped blossoms that are just as attractive to pollinators as people. 3) C. poscharskyana COMMON NAME(S): Trailing Bellflower HARDINESS RATING: H5 FLOWERS: Blue FLOWERING SEASON(S): Summer / Autumn Variously known as the Serbian bellflower and the blue waterfall, this showstopper of a garden specimen produces an abundance of cascading lilac blossoms from spring onwards. Each flower is a perfect star, both in shape and stature. Nonetheless, it should be noted that the cultivar is considered invasive by some authorities. If left to its own devices, it might colonise your garden, so keep a watchful eye on its development. 4) C. lactiflora COMMON NAME(S): Milky Bellflower HARDINESS RATING: H7 FLOWERS: Blue and white FLOWERING SEASON(S): Summer Nicknamed the milky bellflower, C. lactiflora produces attention-grabbing clusters of white star-shaped flowers that carry a purplish tinge to them. This variety is particularly lovely in full bloom, though it does have a tendency to turn brown on fading. As well as adding instant attraction to your garden, milky bellflowers are also practical little critters. That’s because they’re anathema to pests like rabbits and deer, so you can rest assured the surrounding plants won’t be nibbled upon.3 “Campanula lactiflora is one of my favourite bellflowers,” says Colin Skelly, a Horticulturist with nearly 15 years of experience in the industry. “I find it grows well in many garden contexts (except full shade) and has a very long flowering season, especially if deadheaded: it’s not quite bullet proof but not far off. “The only drawback is that, without deadheading, the faded flowers aren’t great to look at, but nobody’s perfect!” 5) C. pyramidalis COMMON NAME(S): Chimney Bellflower HARDINESS RATING: H4 FLOWERS: Blue FLOWERING SEASON(S): Summer The intriguing architecture of C. pyramidalis is what sets it apart from its brethren. Tall spikes of tapered and jagged leaves produce strings of pale blue flowers in the height of summertime, making it the perfect choice for the rear of a garden border. However, it’s not one of the longer-lasting specimens available and is best viewed as a biennial rather than a perennial. 6) C. carpatica COMMON NAME(S): Tussock Bellflower HARDINESS RATING: H5 FLOWERS: Blue and white FLOWERING SEASON(S): Summer One of the easiest alpine species of campanula to grow, the Carpathian harebell is robust and resilient enough to handle the UK climate with ease. It’s immediately identifiable by the large and open structure of its flower heads, which come in brilliant whites and soft pastel blues, among other colours. Pop a selection into the front of a border to add a splash of vibrancy among the foliage. 7) C. glomerata COMMON NAME(S): Clustered Bellflower HARDINESS RATING: H7 FLOWERS: Purple and blue FLOWERING SEASON(S): Summer This devastatingly attractive specimen is commonly known as clustered bellflower and one glance should be enough to understand why. Its upward-facing bell-shaped flowerhead only lasts for a matter of weeks in late spring and early summer – but it’s well worth it. Capable of reaching just over 50cm in height, they’re absolutely at home in an informal cottage garden setting. 8) C. persicifolia COMMON NAME(S): Peach-leaved Bellflower / Fairy Bellflower HARDINESS RATING: H7 FLOWERS: Blue FLOWERING SEASON(S): Summer Despite its common name of peach-leaved bellflower, no part of this plant is actually peach in colour. It remains extraordinarily popular all the same, likely due to its lengthy flowering season. As for the blossoms themselves, they’re cup-shaped and lilac-blue in appearance, with the plant capable of reaching up to 1m in height. C. persicifolia is unfussy about growing conditions but does not deal well with exposed sites and strong winds. 9) C. latifolia COMMON NAME(S): Giant Bellflower / Broad-Leaved Bellflower HARDINESS RATING: H7 FLOWERS: Purple and blue FLOWERING SEASON(S): Summer With a maximum height of 1.2m, C. latifolia isn’t known as the ‘giant bellflower’ for nothing. Its upright structure bears long, oval leaves and nodding flowers whose petals can reach 5cm in length alone. With its blossoms most commonly appearing in light blue or violet, it’s best placed against similarly soft hues in shaded parts of the garden to accentuate its lovely attributes. 10) C. sibirica COMMON NAME(S): Siberian Bellflower HARDINESS RATING: H5 FLOWERS: Purple FLOWERING SEASON(S): Summer We’ve already had Serbian bellflowers – now we have Siberian ones. Native to the upper enclaves of the mountainous regions of Siberia and northern Iran, C. sibirica makes light work of even the worst British winters.4 Of course, it’s summertime when it comes into its own, though. The rough, hairy texture of its foliage and stems is in sharp contrast to the delicacy and daintiness of its bell-shaped blossoms during the warmer months. 11) C. takesimana COMMON NAME(S): Korean Bellflower HARDINESS RATING: H7 FLOWERS: Cream, red, pink and white FLOWERING SEASON(S): Summer With its sagging flowerheads and profoundly intense shades of pink, purple and white, Korean bellflowers are among the most striking of all campanulas. The backdrop of vibrant green foliage serves as a pleasing contrast, only enhancing its appeal. To top things off, C. takesimana comes with a delightful fragrance that’s bewitching to all passers-by. It can be vigorous in its self-seeding habits, so keep it in check to prevent it from taking over your garden. 12) C. garganica COMMON NAME(S): Adriatic Bellflower HARDINESS RATING: H5 FLOWERS: Blue FLOWERING SEASON(S): Summer One of the few varieties on this list whose spread exceeds its height, the Adriatic bellflower forms cushions of bright green leaves in a distinctive heart shape. Come summertime, however, that foliage will be all but invisible as it is smothered in mountains of blue or lilac star-shaped blossoms. Although it reaches just 10cm in height, it will grow outwards quite quickly, so it’s best to give at least 25cm of space on either side of it to express itself fully. 13) C. medium COMMON NAME(S): Canterbury Bells HARDINESS RATING: H4 FLOWERS: Blue, pink and white FLOWERING SEASON(S): Summer Known as Canterbury bells, these hefty flowers are more large than medium. The erect stalks are reddish-brown and hairy to the touch, while the short-stemmed, bell-shaped flowers which perch atop them are exquisite in both colour and shape. They’re not demanding about their growing conditions or the attention you pay to them after establishment, even self-seeding prodigiously. Nonetheless, they’re irresistible to butterflies and bees, so much so that some apiarists even use them to sweeten their honey products. 14) C. punctata COMMON NAME(S): Long-flowered Harebell / Spotted Bellflower HARDINESS RATING: H7 FLOWERS: Blue, pink and white FLOWERING SEASON(S): Summer A native of China, Japan and Siberia, C. punctata’s Latin name can be accurately translated into English as the spotted bellflower.5 That’s down to the mottled appearance of the underside of its petals, but the outer façade is impressive enough in itself. The dramatically long tubular flower heads droop down with no little gravitas, which is only slightly leavened by the dusky pink hue of its blooms. Double-flowering and ruby-red varieties are also available from nurseries and breeders. 15) C. trachelium COMMON NAME(S): Nettle-leaved Bellflower / Blue Devil Bellflower HARDINESS RATING: H7 FLOWERS: Blue FLOWERING SEASON(S): Summer C. trachelium boasts racemes of lavender-blue flowers reaching 3cm in length, making it incredibly easy on the eye. Although the leaves resemble those of the stinging nettle it doesn’t actually sting, so don’t let the common name put you off this beautiful campanula species. References 1. The BRAHMS Project, University of Oxford, Department of Plant Sciences. (n.d.-d). Campanula species. Oxford University Plants. Retrieved March 13, 2023, from https://herbaria.plants.ox.ac.uk/bol/plants400/Profiles/cd/Campanula 2. Campanula portenschlagiana: Adria Bellflower. (n.d.). NBN Atlas. Retrieved March 13, 2023, from https://species.nbnatlas.org/species/NHMSYS0000456767 3. Campanula lactiflora. (n.d.). PFAF. Retrieved March 13, 2023, from https://pfaf.org/user/Plant.aspx?LatinName=Campanula+lactiflora 4. Campanula sibirica. (n.d.). Kew Royal Botanic Gardens. Retrieved March 13, 2023, from https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:141096-1 5. Campanula punctata. (n.d.). PFAF. Retrieved March 13, 2023, from https://pfaf.org/user/Plant.aspx?LatinName=Campanula+punctata
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