Growing
What Is Ericaceous Compost And When Should You Use It? Gardeners Reveal All
IN THIS GUIDE What Is Ericaceous Compost? When To Avoid It Use With Potted Plants How To Make Ericaceous Compost Acidifying Regular Garden Soil Testing The pH Level Of Ericaceous Soil References If you want to grow acid-loving plants in your garden, then ericaceous compost provides an ideal environment for them to flourish. You may have heard of ericaceous compost even if you’ve never used it in your garden. The pH balance of ericaceous compost makes it perfect for growing acid-loving plants. Some of the most beautiful species of plants need acidic soil to thrive, so having ericaceous compost gives you the ability to add a wider variety of plants and shrubs to your garden. Rhododendron love acidic soil! Below is a full guide to ericaceous soil, including its benefits, the types of plants that need it, how to grow your own ericaceous soil and frequently asked questions. What Is Ericaceous Compost? Ericaceous compost is a type of acidic compost that’s used for growing specific types of plants. These can include heathers (‘ericaceous’ is derived from the Latin name for heathers), camellias and rhododendrons but it can be used for pretty much any type of plants that don’t do well in alkaline soil. What Are Its Benefits? There are some great benefits of using ericaceous soil. These include – Great for use with potted plants Creates a perfect environment for acid-loving plants to flourish Minimal feeding is required when good nutrients are used in the mix Retains moisture very well Is easy to make yourself What Plants Need Ericaceous Soil? There are many types of plants and shrubs that prefer ericaceous soil, including – Bilberry Heather Gardenia Trillium Lily of the Valley Trillium Rhododendron Japanese Iris Hydrangea Begonia See a full list of 76 ericaceous plants in this guide. When To Avoid It Although ericaceous compost can be incredibly useful, there are times when it’s better not to use it. Any plants that prefer alkaline soil, for example, would not be suitable for use with ericaceous compost. Although ericaceous soil that’s only slightly acidic might not kill these types of plants, they won’t thrive in the same way as they would in alkaline soil. Use With Potted Plants Ericaceous compost is excellent for use with potted plants for a few reasons. Firstly, you can easily maintain the integrity of the compost when it’s not mixed in with other soil, as it might be in a garden bed or border. Another big advantage to using ericaceous compost for potted plants is that you can grow them in the perfect position for them to thrive. In most cases, acid-loving plants do best in light shade and kept out of direct sunlight, especially during the peak times of the day. Watering & Feeding Plants in Ericaceous Soil Although ericaceous compost typically maintains moisture well, this doesn’t mean you’ll never need to water plants that are in it. It’s very important to keep the soil moist during dry spells by watering regularly. It’s also vital to water any ericaceous plants when you’ve first planted them to ensure the bud survives. When watering plants in ericaceous compost, it’s worth noting that regular tap water is usually alkaline, so using it on them could easily neutralise the soil. To avoid this, it’s usually best to collect rainwater to use exclusively on ericaceous plants. As for feeding, it’s always a good idea to use a good fertiliser if you want your plants to thrive. You can buy plant feed that’s specifically designed for ericaceous plants and it’s certainly recommended you use this since it will contain all the required nutrients for your plants to flower at their best. A lot of the most popular ericaceous plants flower during spring and summer, so this would be the best time to feed them. How To Make Ericaceous Compost Although there are plenty of places you can buy ericaceous compost, it’s quite easy to make it yourself. It mostly comes down to making the soil more acidic than it is alkaline. To do this you can add things like pine needles, citrus peels and leaf mould to your existing compost mix. Another way to increase the acidity of a compost mix is by adding sulphur chips to it.1 It’s important to note that when you’re making your own ericaceous compost, you won’t be able to add anything that might neutralise the pH of the compost, such as calcium or lime. You’ll want to regularly test the pH levels of your compost to ensure that the right level of acidity is maintained. This is particularly important when you’re adding ericaceous compost on top of regular soil since it will lose acidity over time. Regularly adding new acidifying materials will help to ensure that the soil stays at a very high level of acidity. It’s also a good idea to add a layer of mulch. Acidifying Regular Garden Soil If you want to acidify your existing garden soil rather than making your own ericaceous compost, then this is quite easy to accomplish. You can simply add sulphur powder to the soil until it reaches the level of acidity you require. In order to know how much sulphur powder to use, you’ll need to know the current pH level of the soil you’re adding it to. Because sulphur powder is very fine, you’ll want to add it to your soil when the weather is mild. It’s also important that you wear the right safety equipment when using sulphur power. You should always wear safety goggles, a dust mask and gloves when you’re applying it. Testing The pH Level Of Ericaceous Soil How often you should test the pH level ericaceous compost will depend largely on a where you use it. If you put the ericaceous compost on top of regular soil, in a flower bed or border, then it can easily lose acidity over time, so you should test the pH of the soil quite regularly so you can add acidifying materials such as pine cones if you need to. “Using ericaceous compost to amend soil pH is often a losing battle,” says Colin Skelly, a Master Horticulturist. “If you have neutral soil, it might be beneficial to mulch a plant such as Magnolia, which prefers slightly acidic soil, but an alkaline soil will need considerable and continuous amendments to be added to make a change to soil pH. “In these conditions, growing ericaceous plants in pots is a far more sensible use of time and resources.” References 1. Sellmer, J., PhD. (n.d.). Soil Management in Home Gardens and Landscapes. Penn State Extension. Retrieved March 15, 2023, from https://extension.psu.edu/soil-management-in-home-gardens-and-landscapes
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Growing Aquilegia Makes An Excellent Seeding Plant In A Shady Garden
IN THIS GUIDE Overview Habitat & Growing Conditions Aquilegia Plant Care Preferred Soil Watering & Feeding Sunlight Pruning Deadheading Division Common Problems References One genus, a dazzling array of varieties – and so much so that to the untrained eye, Aquilegia species, hybrids and cultivars may be mistaken for entirely different, unrelated flowers. Also called columbine, most varieties display distinctive spurs but what really distinguishes this wildflower is its nearly infinite colour gamut and its blend of exotic yet delicate charm. “I’ve always loved plants like Aquilegia because they are very forgiving,” shares Gardener Sally Flatman. “Even in a shaded garden, they grow and spread.” The columbine is but a common wildflower that has made itself multiple recipients of the Royal Horticultural Society’s Award of Garden Merit. It is a herbaceous perennial that is self-seeding and – to its greater merit – ‘self-hybridising’. Aquilegia atrata: the dark columbine wildflower This is because it cross-pollinates and inter-breeds. So if you do end up growing these lovely plants, consider not deadheading them all, instead letting them go to seed – and then take pleasure in the new strains, shapes, and hues that adorn your garden the following year! “If you grown the common Columbine species, Aquilegia vulgaris, then it will self-seed readily around your garden, finding the most favourable spots,” shares Colin Skelly, a Master Horticulturist. “If your neighbour has a cultivated form or if you choose different species or cultivars, they will hybridise readily and produce seedlings unique to your garden. “If there is one you really like you can propagate it by division as the seed won’t be true to the parent plant.” Overview Botanical Name Aquilegia Common Name(s) Granny’s Bonnet, Columbine Plant Type Perennial Flower Native Area Various Hardiness Rating H5 Foliage Herbaceous, pale green leaves Flowers Varied flowers When To Sow March, April, May Flowering Months May, June When To Prune June, October, November Variously described as ‘beautiful’ and ‘stunning,’ yet also as a ‘shy’ ‘cottage garden’ denizen, the columbine is self-evidently many things to many people. The larger species sprawl out to 75cm or more in diameter and grow to be as tall; Aquilegia vulgaris or the common columbine reaches a full metre in height. However, dwarf cultivars are petite and are ideal for compact spaces. Dwarf columbine Aquilegia vulgaris ‘Nana’ grows to only 25cm and Aquilegia buergeriana ‘Calimero’ not even to 20cm. Notwithstanding such diversity, for the most part the flowers have five sepals and five petals, and even five pistils. Aquilegia flowers are not only visual delights for you and I; they are magnets for honey-bees, bumble-bees, butterflies, and hummingbirds. Hence, a bed or two of columbine will add an extra layer of nature’s beauty to your garden. With about 130 species and many more hybridised cultivars to choose from – and with such a profusion of floral ‘styles’ at that – you’ll be spoilt for choice.1 Belying its delicate and exotic blooms, columbines are one of the plant world’s good sports; these low-maintenance charmers get by on the most basic care and are not particularly picky about soil and growing conditions. This quality makes them especially suitable for casual gardeners with limited time. Here are camera angles of a beautiful Aquilegia variety I grew from seed in an outdoor planter earlier this year: You may notice how the flower stems rise high above the unfurling foliage (which is beautiful in its own right) and the highly unusual shape of the flower heads. Habitat & Growing Conditions Woodlands, riversides, hillsides, and meadows in the temperate and cool regions of the Northern Hemisphere are the favoured habitats of Aquilegia.2 The plants are further inclined to dappled sun, as on the rim of a woods, or partial shade, as near the base of a rocky outcropping. While some Aquilegia fare well in dry soil, the greater part thrive in moist, well-drained soils. Columbine season is from late spring to early summer, between the early spring bulbs and the summer flowering season. Aquilegia Plant Care Aquilegia are remarkably unfussy and sporting plants, with most varieties making do with whatever they get. However, to get the best out of your plants, tailor the growing conditions to their liking. Preferred Soil I find that these plants prefer rich soil; humus or loam mixed with sand or chalk is best but dense clay is to be avoided. The soil should not be allowed to dry out and should be kept moist but it must drain well. The ideal pH range is 6.0 to 7.0 though a ±1 swing will be perfectly acceptable to your columbine. Watering & Feeding In temperate zones twice-weekly watering is sufficient when grown in pots, but in warm climates or during hot weather more frequent watering may be necessary. Most varieties do well without any fertiliser; that said, feeding your plant with water-soluble 5-10-5 fertiliser will result in lusher foliage and brighter, healthier blooms, particularly for pot-grown plants. Sunlight Though most columbines do just fine in full sun, most do even better in dappled sun or partial shade. Plant them close to taller plants in sunny climes to provide shade for at least part of the day. Columbine ‘Crimson Star’ In the UK these plants are H7 hardy, meaning they are fully resilient against frost and freezing across the British Isles.3 Pruning For many plants, pruning is a ‘best practices’ requirement but for Aquilegia it is more of an optional, strategic decision. On an ongoing basis, you can pinch off dead flowers or snip them where the flower stalk meets the stem. Soon after the initial bloom cycle you can cut the stems to their respective halfway points and trim some of the foliage. Not only will this improve the plants’ appearance, but it may also induce a welcome second round of blooms in early summer. After any second bloom or before the end of summer, say in July, prune the plant down to its basal leaves; these are the larger leaves that issue from the main stem just above the soil. This pruning will redirect nutrients to the roots instead of to unproductive stems, thereby building resources for the following year. Deadheading When the initial flowering cycle ends, you can deadhead by cutting off the stems to the basal leaves. The first reason is to prevent inter-pollinated self-seeding, should you so wish, by this happily inter-fertile genus – if you would rather have established species and cultivars in your garden instead of random and unpredictable new strains, then you would deadhead. The second reason is to enhance plant vitality as it will result in bigger blooms the following year, and also to increase its productive lifespan as plant resources will not be spent on producing seeds. Deadheading is a special form of pruning, having to do with prompt removal of spent blooms. If you want to deadhead, cut terminal flowers about 1cm above the leaves below it. Cut lateral flowers where their stalk joins the main stem if the main stem has blooms further up the main stem, but if not then cut off the main stem itself at a point just below where the spent bloom’s stalk joins it. A happy compromise might be to deadhead somewhat more than 50% of the flowers after the second or last bloom cycle while letting the rest go to seed. Because columbines tend to wither and die in about four years, you may wish to take advantage of its propensity to self-seed. Division Remember that if you already have Aquilegia then you can ‘buy’ this plant from home by division (or separation). It is not easy but quite possible: Choose a big, spread-out clump in early spring and dig very deeply in a circle all around the roots. Pull up the plant with the soil around the roots, divide the roots with a clean sharp knife, leaving as much soil as you can around the roots, and replant promptly. Apply a mulch of compost around the divided plants. Note that divided Aquilegia may take some time to gain vitality. Red columbine (Aquilegia formosa) wildflower You can divide an Aquilegia plant every other year. Common Problems This generally healthy and trouble-free plant has but two ‘enemies’: powdery mildew and leaf miners. Powdery Mildew Powdery mildew attacks columbine when it is wet and rainy or when you have warm days and cool nights. To combat it, cut off the affected parts of the plant, doing so to a couple of centimetres from soil level if need be. Give the plant plenty of sun and ample air circulation to help it avoid another bout of powdery mildew. Leaf Miners If you see a leaf miner infestation, you can wait until the blooms are spent before cutting down and destroying affected parts of the plant or you may do so immediately. References 1. Aquilegia. (n.d.). Kew Royal Botanic Gardens. Retrieved April 11, 2023, from https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:325954-2#children 2. Columbine. (n.d.). Plant Atlas. Retrieved March 9, 2023, from https://plantatlas2020.org/atlas/2cd4p9h.yc6 3. Aquilegia vulgaris. (n.d.). Royal Horticultural Society. Retrieved March 9, 2023, from https://www.rhs.org.uk/plants/100859/i-aquilegia-vulgaris-i/details
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How To Plant And Grow Honeysuckle: 'It's Superb At Creating Habitats For Wildlife'
IN THIS GUIDE Overview Common Varieties How To Grow Honeysuckle Ongoing Honeysuckle Care Common Problems Container Growing Trellis Growing References You may not know it by its proper name, Lonicera, but you’ve almost certainly heard of its more common moniker: Honeysuckle. This deciduous or evergreen climber is widely grown in the UK, and is often associated with quaint country cottages and romantic archways. Honeysuckle is well-known for its fragrant, tubular flowers which appear in clusters, often for the duration of summer. The blooms come in a range of colours, including yellow, orange, red, pink and white, and give way to brightly coloured berries in the autumn. “Honeysuckle is superb at creating habitats for wildlife, especially if you let it grow a bit wild and tangled,” shares Garden Writer Nic Wilson. “Ours harbours nesting blackbirds and collared doves. It produces nectar-rich flowers which attract a range of pollinating insects including moths and, of course, there are berries for the birds. “I also love to watch house sparrows and starlings pulling the bast (inner bark fibres) off our honeysuckle stems to use in their nests.” Lonicera x brownii ‘Dropmore Scarlet’ This pretty and popular plant is easy to grow in the UK and offers big rewards for little effort. If positioned, grown, and trained correctly, it makes a quick and attractive way to cover a fence or garden wall. Choose an evergreen variety, and you’ll benefit from year-round foliage. Overview Botanical Name Lonicera Common Name(s) Honeysuckle Plant Type Climber / shrub Native Area Temperate and Subtropical Northern Hemisphere Hardiness Rating H5-H6 Foliage Deciduous or evergreen, twining stems Flowers Tubular or bi-lipped flowers, often fragrant When To Sow February (Deciduous Types), March, April, October, November Flowering Months June, July, August, September When To Prune April, May Lonicera honeysuckle is a member of the Caprifoliaceae family and is thought to be native to nearly all of the temperate Northern Hemisphere.1 It most commonly flowers from early summer to early autumn – the blooms can be one colour or multi-coloured, and either fragrant or scentless. The plant then produces berries, which are red, blue or black in colour. Honeysuckle can be deciduous, semi-evergreen or evergreen, depending on the variety. Deciduous species tend to put on a more spectacular display in the flowering season, but evergreen variants provide foliage cover year-round. Honeysuckle is a great way of encouraging more wildlife into your garden. The strong scent attracts pollinating moths at night, the white admiral butterfly relies on it for food as a caterpillar, dormice find shelter in its foliage, and the berries are attractive to many birds. Common Varieties There are thought to be over 180 varieties in the Lonicera genus.2 Well-known varieties of these evergreen climbers include Lonicera japonica (Japanese honeysuckle) which produces sweet-scented white flowers from May to August – and L. sempervirens, which has fragrant orange-red, trumpet-shaped blooms. L. sempervirens L. fragrantissima (Winter Honeysuckle) is a deciduous shrub and displays fragrant creamy blooms from January to March. L. fragrantissima Not all honeysuckles are climbers – some are shrubs or bushes. Some species of honeysuckle, including L. japonica, are also considered invasive outside of their native range, due to their aggressive growth and dense foliage, which can crowd native plants. L. japonica Other names for honeysuckle are woodbine – which refers to L. periclymenum, and indicates that this species used to grow in woodlands – and twinberry, which refers to how the flowers often grow in clusters of two. How To Grow Honeysuckle Honeysuckle is widely available in the UK, and can be purchased from most garden centres, nurseries or from a wide array of online retailers. Plants are available to purchase year-round and usually come in pots with canes, to support the stems. L. caerulea var. edulis Ideally, shop in a physical store, so that you can choose a plant that looks healthy with no visible signs of problems, and at least 2 strong shoots coming from the base, which you will be able to tie to a trellis. You can also purchase or harvest honeysuckle seeds, although these will require refrigeration or outdoor cold treatment for 1-3 months prior to planting, in order to germinate. After sowing, keep the pots at around 15°C until the seeds begin to sprout. Planting The best time to plant honeysuckle depends on whether you’ve chosen a deciduous or evergreen variety. Deciduous species should be planted in late winter, whilst evergreens flourish best when started in spring or autumn – refrain from planting in waterlogged or frozen ground. Ongoing Honeysuckle Care Honeysuckle is generally a hardy plant, but thrives best in partial shade – it can cope in full sunlight, but may suffer from scorched leaves. Similarly, it can survive in fully shaded areas, but it will probably not produce flowers. Soil Requirements The plant prefers free-draining, damp soil, that is neither too dry or waterlogged. Add mulch to the soil once planted, and every spring thereafter to improve soil quality, prevent dry roots, and reduce the risk of powdery mildew. You can also use a general fertiliser, such as blood, fish and bone, annually. Watering Regular watering is required during the plant’s first year of growth, but once it is established, it will only be necessary during particularly dry periods, or hot summers. Support You will need to provide honeysuckle with suitable support in order for it to climb. This could be a wall, fence or archway, and there will need to be fixed wires or a trellis just in front of the wall, onto which you can tie the limbs during the initial growing period. Pruning The first time you should trim your honeysuckle shoots is upon planting, to encourage strong new growth which you can tie to your trellis or support structure. Aim to cut back around half of the existing growth at this time. From then on, prune your Lonicera honeysuckle annually, to keep it in shape and prevent it from taking on an overgrown appearance (take care not to dislodge any nesting birds). The best time to prune depends on the variety of honeysuckle. For species that flower early, prune after flowering, cutting back the flowering shoots by a third. Do not remove the dying flower heads, as this will discourage autumnal berrying. For late flowering varieties, prune in spring, before flowering – stick to a light pruning, so as not to reduce blooming. Remove any damaged shoots, and gently thin out bushy areas to create a more coiffured appearance. Cutting Back Honeysuckle You may need to completely cut back honeysuckle that has become overgrown and out-of-control, or a plant that has bare branches at the bottom and a congested top, which cannot be thinned out. Congested growth is a common cause of powdery mildew, as it restricts air circulation around the plant. To re-start a particularly congested honeysuckle, prune it back hard in late winter to around 60cm. Give it a mulch and a good watering, and the honeysuckle will respond with strong new shoots in spring, which you can then train to a trellis. It should start to flower again in a couple of years. Common Problems Honeysuckle is generally a hardy plant and does not suffer from many common pests or problems. There are, however, a few to watch out for, including powdery mildew and aphids. Powdery Mildew Powdery mildew is a fungus which causes the leaves of the honeysuckle to turn grey and curl. It usually occurs when the root system becomes too dry during hot weather. For this reason, it’s important to water the plant at the roots during dry spring weather and add mulch to the honeysuckle’s soil, to encourage moisture retention. This is particularly true if your honeysuckle is growing against a wall, as the soil there tends to be drier. Aphids Check your plant regularly for visible signs of aphids – they are usually easily spotted in spring. Small amounts of aphids can often be wiped away using a cloth or washed off with water. Severe infestations may cause leaf distortion and sooty mould. Prune infested shoots, and if necessary, use an insecticide – although this should always be a last resort, as it can be severely damaging to wildlife and pollinators, such as bees. Container Growing Honeysuckle can be grown in pots, although it will not grow in the same prolific way as in garden soil. The advantage of container growth is that you can move the plant around, and enjoy its fragrant scent in all areas. Choose a smaller variety that is suited to container growth, such as L. fragrantissima. Make sure the container has good drainage and is deep enough to keep roots cool. Plant the honeysuckle in rich compost, and water the soil regularly – remember that you will need to insert canes or a trellis to support your climbing plant. Trellis Growing To grow honeysuckle on a trellis along a wall, you should position the trellis panels 5-10cm in front of the wall, to allow for better air circulation around the plant. Dig a hole 50cm away from the wall (make it twice as wide but equal in depth to the pot your honeysuckle is in) and add some compost. Loosen the roots from the root ball of the plant, before placing it in the hole and refilling. Mulch the ground and water thoroughly. Tie the honeysuckle shoots to the bottom of your trellis in a fan shape. As the plant grows, use more plant ties to guide it in the right direction. Continue to do this, watering regularly, and watch as your honeysuckle starts to establish and cover the trellis (and your wall) with its dense green foliage. References 1. Lonicera. (n.d.). Kew Royal Botanic Gardens. Retrieved March 17, 2023, from https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:30006074-2 2. Lonicera (shrubby species and primary hybrids). (2020, March 25). Cambridge Botanic Garden. Retrieved March 17, 2023, from https://www.botanic.cam.ac.uk/the-garden/horticultural-collections/national-plant-collections/lonicera-shrubby-species-primary-hybrids/
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Pyracantha 'Firethorn': Grow This Plant To Enliven An Otherwise Dull Evergreen Hedge
IN THIS GUIDE Overview Habitat & Growing Conditions Pyracantha Varieties How To Grow Pyracantha Pyracantha Care Espalier (Wall Training) Pyracantha Common Problems References Pyracantha is an ornamental, evergreen shrub, characterised by its flaming red and orange berries, and sharp thorns – hence its other name, ‘Firethorn’. It also produces cream-coloured blooms in summer, making it a great way to introduce colour to your garden year-round. This is a fully hardy climbing or hedging plant, which grows well in the UK climate. It makes an attractive and low-maintenance addition to almost any garden – and can be grown either as a freestanding shrub, or trained to grow along a wall or fence. “This plant can really enliven an otherwise dull evergreen hedge with the unusual density of its flowers and fruits – few other plants will do a similar job so well,” says expert Horticulturist Peter Lickorish. Reasons that make it an excellent choice for a hedging plant include that it’s fast-growing, has dense, evergreen foliage, and can reach heights of 4 metres if left unchecked. Plus, its sharp thorns can work to deter unwanted visitors from entering your property! Overview Botanical Name Pyracantha Common Name(s) Firethorn Plant Type Shrub Native Area Europe, South-East Asia, China and Taiwan Hardiness Rating H6 Foliage Evergreen Flowers White flowers, bright orange/red berries When To Plant January, February, March, October, November, December Flowering Months July, August, September When To Prune March, April Pyracantha is native to Europe, South East Asia, China and Taiwan.1 There are several species within the genus, which is part of the rose (Rosaceae) family. It is a dense, evergreen shrub that grows quickly – the plant produces white or cream-coloured blooms in summer and red, orange or yellow berries in autumn and winter. The largest varieties can grow to around 4m x 4m in size. Due to its size, density and sharp thorns, it is often considered a natural form of security. Whilst discouraging unwanted guests, pyracantha is also great for tempting more wildlife into your garden. The blooms attract pollinators, whilst the red berries of autumn appeal to birds. The thorns also provide protection for any native wildlife nesting or sheltering within its foliage. Habitat & Growing Conditions The natural habitat of pyracantha stretches from south-east Europe and the Mediterranean to south-east Asia. The plant is well-accustomed to high daytime temperatures, and low night-time ones – it can tolerate partial shade, but will flower and berry best when grown in full sunlight. Pyracantha grows in all soil types, including clay soil, as long as it has good drainage. The plant is tolerant of drought but does not like to be waterlogged, so prefers its soil to be dry rather than too wet. Pyracantha Varieties Some varieties are more suited to being freestanding, whilst others are better for training and hedging. ‘Red Column’ For example, ‘Red Column’ is a particularly fast-growing, thorny variety, with bright red berries and a height of around 3m, all of which makes for a great hedge. ‘Santa Cruz’ ‘Santa Cruz’ is smaller, reaching 1.5m, and is well-suited to container growth or ground cover. There are also newer varieties of pyracantha that have been bred to be resistant to some of its most common diseases. ‘Golden Charmer’ For example, the ‘Golden Charmer’ and ‘Teton’ varieties are resistant to pyracantha scab, and the ‘Saphyr’ series is resistant to both this and fireblight. How To Grow Pyracantha Pyracantha is a popular plant in the UK and is widely available. You can purchase seeds or cuttings from garden centres, specialist growers or online retailers. Note that if buying seeds, they will require 3 months of cold stratification before they will germinate. If, as is advisable, you are buying a potted plant for transplanting, look for one with a good shape, and a decent colouring of berries, indicating a healthy plant. Check it over to make sure there are no signs of pests or disease. There are many varieties of pyracantha, and you can choose based on whether you want to grow it freestanding, trained or as a hedge, as well as what colour of berries you want. Pyracantha Care Pyracantha can be planted year-round, although the best time is in the autumn or winter months. Exposure Try to find a sunny or partially shaded spot for it, as full shade will hamper berrying. It can tolerate high and low temperatures, (down to -15°C), as well as wind – although again, this may hamper growth. Soil Requirements Pyracantha will grow in most soils, but it prefers a fertile, deep loam – prior to planting, enrich the soil with a bucket of well-rotted manure and a balanced fertiliser, mixing it in with a garden fork. You can also feed the plant annually with a similar mix in spring. Watering You should water establishing plants frequently during the growing stages. Once the plant is established, it requires little maintenance, and will likely only need to be watered during particularly dry spells. It does not like to be waterlogged, as it is susceptible to root rot, so the soil should have good drainage. Add coarse grit to heavy or clay soil if necessary. Espalier (Wall Training) Pyracantha To espalier pyracantha, you should first fix horizontal wires across your wall, so you have something on which to attach the plant limbs. Plant your pyracantha approximately 50cm away from the wall, in springtime. This ensures the roots are not in any dry shade or rain shadow from the wall. This ensures the roots are not in any dry shade or rain shadow from the wall. Using soft plant ties or twine, tie the centre shoots vertically up the wall, and the side shoots at a 45° angle. Allow the plant to grow over summer, then re-direct the shoots horizontally in autumn. “Training shoots horizontally often reduces vigour, but increases flowering and fruiting,” says Peter Lickorish. Common Problems There are several diseases that are common to pyracantha. Pyracantha Scab Pyracantha scab is a fungal disease that causes unsightly black spots on the shrub’s leaves and berries, shrivelled flowers, and leaf and flower dropping. If you notice any of these symptoms, you should cut back the infected parts (even though this will mean fewer flowers the following year). You should also ensure that any infected material, such as fallen leaves and berries, is raked up and removed from the garden, as this is how the fungus survives over winter. In severe cases, use of an appropriate fungicide may also be required. Fireblight Another common problem is fireblight. This is a bacterial disease that thrives in wet and warm weather. It kills shoots, wilts flowers, and causes your plant to take on a ‘scorched’ appearance, with browned wood and cankers. Treatment is non-chemical only, and involves pruning the affected branches back to expose healthy wood, cutting back at least 30cm past any damage, and removing any remaining new flowers before they open. This is often how the bacteria enters the inner bark. Both pyracantha scab and fireblight will ravage the plant from spring to autumn. Pests Common pests include the pyracantha leaf-mining moth, and aphids. The leaf-mining moth lays its eggs on the plant, and the caterpillars then feast on its leaves from the inside, causing silvery ‘mines’ of discolouration. This is most likely to occur during late winter to early spring. Whilst it may look unsightly, most of the affected leaves will drop off and be replaced in spring, and the process has little effect on the overall health of the plant. Lack Of Berries Lack of berries is also often reported by pyracantha growers. This is usually a result of unfavourable growing conditions, such as frost or cold weather, drought or lack of food. Make sure to water your plant during dry spells, and try adding a high-potassium plant feed to the soil in spring. References 1. Pyracantha. (n.d.). Kew Royal Botanic Gardens. Retrieved March 23, 2023, from https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:30154448-2
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This Is How To Grow Cordyline ‘Cabbage Palm’ With Advice From Peter Lickorish
IN THIS GUIDE Overview Cordyline Plant Care Habitat & Growing Conditions How To Shorten A Cordyline Common Problems References Although Cordyline is a genus comprising 23 species of woody plants, where gardeners are concerned the name connotes a handful of ornamental species.1 They are of widely varying sizes, most with lanceolate leaves fanning outward radially and bearing clusters of tiny flowers. The ‘Cabbage Tree’ and its variants are perhaps the most well-known and also the most popular species. Cordyline species are fairly diverse in both size and appearance. Many Cordyline are a good choice for borders and for accents, they are used to set off brightly-coloured flowers, and they make artistic elements in a rock garden. Overview Botanical Name Cordyline Common Name(s) Cabbage Palm Plant Type Shrub Native Area Eastern Australia, New Zealand & Melanesian Islands Hardiness Rating H3 (for species grown outdoors in the UK) Foliage Leathery leaves in a lance shape Flowers Fragrant cup-shaped flowers When To Sow April, May Flowering Months June, July, August They can be placed in the corners of your patio, and they can just as well be placed in the corners of your drawing room. “How happy they are outside, and for how long, will depend on their hardiness,” shares Master Horticulturist Peter Lickorish. “Those with a hardiness of H1 are predominantly houseplants.” Cordyline are evergreen perennials and many of them resemble miniature palm trees. The leaves tend to be lance-shaped and pointed, radiating outward, and growing in tiers on the central stem. They are among the most distinctive and striking of all leaves. While many are some shade of deep green, other species’ and cultivars’ foliage have eye-catching hues. Young leaves of some species are hot pink, others are bordered and striped with yellow and rose, still others are a chocolatey maroon. But Cordyline is not only about its attractive foliage: in summer, most species bear panicles or other sprays of small white or light-coloured flowers. These are adored by bees. Come autumn, the panicles and sprays transform into tassels of small berries, usually red and sometimes purple. Because Cordylines are perennials and, once planted in conditions to their liking, require very little care, they are an excellent choice for the casual gardener who wants to plant once, especially outdoors, and then leave the little beauties to their own devices. Cordyline Plant Care In the main Cordyline cultivars prefer moist but well-drained soil and a humid atmosphere. While you certainly should not overwater, do not allow the soil to dry out especially during summer, dry weather, or the growing season. Preferred Sunlight These plants’ preference for sun or shade varies quite widely between even related species. C. australis does best in full sun to very light shade but C. fruticosa prefers part shade, with indirect sunlight being best. As a general rule, species and cultivars with green leaves have a greater preference for sun; in contrast, the more multi-coloured the foliage, the greater the preference for shade and indirect sunlight. Soil & Fertilising Most Cordyline plants do best in rich soil. Cordylines have a distinct preference for moist soil and do not do well in dry soil. Some Cordylines do well even in wet soil but it should not be waterlogged, especially in winter, when their tolerance for dampness is at its lowest. The soil’s pH should be between slightly acidic to neutral; a good range is 6.0-7.0. “If potting your plant, use commercial organic soil or a mix comprising close to 50% loam and the rest peat-free compost, with some added grit,” adds Peter. Choose a fertiliser with a balanced N-P-K ratio with which to fertilise potted Cordyline at monthly intervals during the growing season. “Those grown in the ground rarely need feeding, though mulching before winter can be beneficial,” Peter says. Do not fertilise at all during winter. Habitat & Growing Conditions Cordyline species, as multifarious as they are, thrive in diverse conditions. Take the Cabbage Tree itself – they can grow in soil conditions ranging from low-lying swamps to rocky hillsides in New Zealand where they once covered vast tracts of land including riverine areas. In contrast, C. congesta or the Narrow-Leaved Palm Lily sprout next to rainforests and within eucalyptus forests. Other Cordylines thrive in river valleys. However, what is non-negotiable for seedlings and young plants is ample sunlight and abundant water. Cordyline species, as tropical and sub-tropical plants, prefer warm climates. Even so, most Cordylines are right at home in distant lands like England and Japan where they are sought-after architectural plants. These evergreens are surprisingly hardy; indeed, some species and cultivars tolerate even sub-freezing temperatures. Consider: though the preferred temperature range for both C. australis and C. australis ‘Atropurpureum’ is 18-22°C, the former can tolerate temperatures all the way down to -7°C and the latter to -5°C provided the plants are mature. How To Shorten A Cordyline Where Cordylines are concerned, your watchword is, “be merciless!” – and that’s because Cordylines can get out of hand and grow tall, gangly and straggly, but they are very forgiving of the knife. Simply – and mercilessly – cut back the entire plant to reduce and control its size during the growing season. Use a pair of secateurs or loppers (after cleaning the blades with diluted rubbing alcohol) to cut off one or more heads and leave about 40cm of the main stem(s). Fresh growth will soon be visible, but you can help this along by applying some blood fertiliser or bone fertiliser. Repeat the process as and when necessary and you will end up with a Cordyline whose size and shape is to your liking. However, if, after being cut back, the plant has not grown tall but has spread too far laterally or looks unkempt, prune it. Do not cut off the entire head during the rainy season or in cold weather – during periods of rain or cold, the plant needs its leaves to survive. “Cordyline trunks are among the most distinctive features of this plant once mature,” shares Peter. “You can either cut old, dying leaves back to leave short stubs a couple of centimetres long, which make a geometric pattern cloaking the trunk, or peel the leaves off to expose the trunk underneath. “I can’t decide which I prefer with mine so have done both, but either way, it’s a vigorous plant. “Scarcely a decade old, mine is several metres high and puts on extensive re-growth each year. “Growing bolt upright, it makes a good focal point with a slender canopy, ideal for underplanting.” Common Problems Aphids, mealybugs, scale, thrips, and spider mites are the main pests and problems that Cordyline owners may need to tackle. Spider Mites Be vigilant, especially on indoor Cordylines, as spider mite can cause unsightly brown spotting on the leaves. This is a result of the mites sucking sap. If you catch a spider mite infestation early, it may have affected only a small part of your plant. If so, cut off that part, but if the entire plant is affected, it will be difficult to eliminate the mites and the wisest course may be to give up that plant. Otherwise use pyrethrum to control populations which have begun to produce silk webbing. Mealybugs If your mealybug-infested Cordyline is outdoors, release beneficial insects like lacewings and Mealybug Destroyers on the plant. They prey upon mealybugs. “Inside, some levels of damage can be tolerated, but pyrethrum is a successful treatment. Aphids Aphids are a serious threat because they breed so rapidly and in such numbers that they can outrun your efforts to exterminate them. Wipe or spray any major aphid infestations off with water, to prevent secondary problems with sooty mould. They are more likely to be found indoors. Thrips To control a localised infestation of thrips, which can severely weaken plants by their sap-sucking, hang suitable sticky traps to minimise damage. For bigger or stubborn infestations, spray Spinosad once only and not on a recurring schedule. Also deploy minute pirate bugs and lacewings, the natural predators of thrips. How Do You Know When Your Cordyline Is Dead? You need to be sure that your Cordyline is dead because sometimes they play possum! If your Cordyline has lost all its leaves, continue caring for it and be patient. If new shoots sprout from the trunk itself, the plant is not dead. But if no shoots sprout from the trunk or from the soil level, the plant is probably dead, especially if the trunk or core of the plant feels mushy. If the main stem or trunk feels soft but firm lower down, cut it back to the point where it is hard and firm – do so only in the summer. Then keep a watch on the plant to see whether or not new shoots sprout from the remainder of the trunk. References 1. Cordyline Comm. ex R.Br. (n.d.). Kew Botanic Gardens. Retrieved May 22, 2023, from https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:24159-1#children
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Growing 'Exotic And Extraordinary' Passionflower With Breeder Myles Stewart Irvine
IN THIS GUIDE Overview Habitat & Growing Conditions How To Grow Passion Flower Passiflora Care Common Problems References You’ve probably heard of passion fruit, but what about passion flower? Passion flower (Passiflora) is a flowering vine with hundreds of variants, one of which (P. edulis) produces the colourful, seed-filled passion fruits you might find in your fruit bowl. All varieties of this striking vine display dark green leaves and distinctive, tropical-looking flowers, with flat, open petals, showy stamens and hair-like coronas. Passionflower comes in many colours, including purple, pink and blue, and can add an ornamental, exotic look to your garden. For this guide, we consulted Myles Stewart Irvine, an expert grower and breeder of Passiflora. “I randomly bought a Passiflora ‘Amethyst’ from a garden centre in the late 1980s,” says Myles. “That started my lifetime fascination with these exotic and extraordinary plants.” Overview Botanical Name Passiflora Common Name(s) Passion Flower Plant Type Climber Native Area Americas Hardiness Rating Varies by type Foliage Evergreen, simple leaves Flowers Showy flowers When To Sow April, May, September, October Flowering Months May, June, July, August, September When To Prune March Passionflower originates mostly from Central and South America, with the exact locale depending on the variety.1 Some species are also native to the lower areas of North America.2 “There are about 550-600 species, mainly climbing vines plus a few trees, as well as hundreds of hybrids,” explains Myles. “As climbing vines, they grow chaotically, swarming over whatever they can. Out of this chaos, they produce the most amazing intricate flowers, some of which are incredibly perfumed.” Two of the most well-known varieties are P. edulis, a tropical, perennial vine which produces purple and white flowers, as well as edible purple and yellow passion fruits, and P. caerulea, a deciduous or semi-evergreen climbing shrub, with blue flowers. These varieties can grow to 1.5-8m in height respectively. “The common Passionflower, Passiflora caerulea, has blue and white flowers and orange fruit later in the season,” says Myles. “This is a great plant to start with, as it is not fussy about anything and is free flowering from May to October. P. ‘Betty Myles Young’ Passiflora flowers are very distinctive – they are approximately 10cm wide, with a flat petal base, protruding stamen, and colourful corona (delicate, hair-like appendages) between the flower’s corolla and stamen. The flowers are extremely attractive to pollinators (they are great for encouraging butterflies into your garden), but usually, only remain open for a day. Today, passion flower is also known as ‘Passion Vine’, ‘Apricot Vine’ and ‘Maypop’ – due to the fact that it usually flowers in May. Habitat & Growing Conditions The native habitat of passion flower stretches from southern USA, through Central America and down to Brazil in South America; some varieties are also found in South East Asia and Oceania. Although it originates from warm climates, many varieties are hardy, and can do well in much milder climates, including the UK. In some warmer areas, the plant can even become invasive.3 Passionflower grows in anything from indirect to full sunlight; it favours a moist, fertile soil, with a neutral pH and adequate drainage and it does not like to be water-logged, as this can lead to wilting, fungus and root rot. How To Grow Passion Flower You can purchase passionflower seeds and seedling plants from garden centres, nurseries and online retailers. The most popular species available in the UK is the hardy, blue-flowered P. caerulea – if you want another variety, you may need to shop around to find a specialist grower. Growing From Seed Growing passion flower from seeds is not the quickest or easiest option. Seeds sprout best when they are fresh, and it is recommended to soak them overnight prior to planting, to break down the seed shell and assist with germination. Even so, it can take seeds up to a year to sprout. “Though growing from seed can be great fun, in practice the seeds are often slow to germinate, taking many months to do so – if they come up at all,” says Myles. “The seedlings can be weak and variable too, and seed for sale may often be old or described incorrectly. “So, it is far safer to pay more money and buy established plants from reputable suppliers, either garden centres or more specialist nurseries.” Many garden centres and supermarkets will only sell passion flower in season, when the plant looks its best. To purchase passion flower out of season, find a nursery that grows them outdoors, meaning the plant should be hardier, and able to withstand being planted in colder weather. “There is only a limited range of hardy passiflora that do well in the UK climate outdoors year-round, but even then they will do best in more southerly areas,” Myles warns. If you know someone with a passion flower, it is also possible to propagate them from cuttings or layered shoots. Passiflora Care Hardiness It is important to note that the variety of passion flower you are growing will affect the way you care for it. For example, P. caerulea is resistant to frost, so can be grown outside (although it may still require cover in winter). “Another good option to grow outside is the purple-flowered Passiflora x violacea, which is an inter-species hybrid (a cross between) P. caerulea and P. racemosa,” shares Master Horticulturist Dan Ori. Many other species are not hardy to freezing temperatures, and should be kept above 5°C, or, in the case of tropical varieties such as P. edulis, above 10°C. These plants need to be brought inside during winter – make sure to research your chosen variant prior to purchasing, so you know of its specific requirements. Preferred Aspect “Bearing in mind that there are hundreds of different Passionflowers, some, of course, need specialist care,” Myles explains. “However, those most widely available love a sunny, south-facing location, perhaps in thin beds hard up against a brick wall or in terracotta pots.” If you’re growing your passion flower outside, always try to choose a sheltered spot, with either full or partial sunlight, avoiding areas that are entirely shaded. Passionflower can also be grown in a sunny area indoors, or in a greenhouse – although some protection may be needed to avoid leaf burn in summer. You can either plant it in your garden borders, or grow it in a container. Growing passion flower in a container is advisable, as it means you can move it around, control the amount of sunlight it gets, and bring it inside to protect from frost. It will also help prevent your passion flower from spreading and becoming invasive. Soil Requirements Depending on the variety, passion flower is generally a hardy plant, and will thrive in pretty much any soil type and pH. It does, however, prefer its soil to be fertile – when planting in a container, do so in a high-quality, peat-free compost. “They love a free-draining soil mix, so add rubble, sharp sand and horticultural grit as appropriate,” suggests Myles. “They are also greedy feeders and, when growing at full speed, will benefit from a good general-purpose liquid or prolonged release fertiliser, especially when grown in pots. “For the most part, I use chicken manure or seaweed pellets for my plants.” Watering As far as watering is concerned, you should keep soil moist throughout the summer growing season. Do not allow it to dry out, but make sure it’s not waterlogged either – the soil should have good drainage. “Over winter, the roots can easily rot,” says Myles. “Even in summer, a thorough soaking weekly is better than daily.” With this in mind, you should reduce watering during winter. Support “Passion flowers will want a trellis, wire or similar to climb up,” explains Myles. “If you’re growing it in a pot, a tripod of 5-foot bamboo canes will do fine.” You can encourage it to do so by using soft plant ties to attach the branches to the support, at regular intervals, whilst it’s growing. Pruning “In a tropical climate, you can prune passion flowers anytime and get away with it, but in the UK, it is best to leave as much greenery on them as possible to help them get through winter,” Myles shares. “The time to prune is in late spring when regrowth has started.” Trim back the growing shoots, to encourage the plant to branch at the base, and grow in a more attractive shape. “Leave at least two long stems with leaves on until the whole plant has new growth,” says Myles. “At that stage, you can then cut back the two long stems and the plant will be fine.” This is also the time to start training your plant to grow along a fence or trellis, by tying its shoots periodically along the fence. Once your passion flower reaches maturity, you should prune it every spring, to encourage flowering. Take this opportunity to trim back any extended shoots, re-shaping it into your desired form. If growing outside, you should also make sure to remove any limbs damaged by frost. Common Problems There are several problems that are common to passion flower. Cucumber Mosaic Virus One to watch out for is Cucumber mosaic virus (CMV), which can cause a mottled yellow appearance, stunted growth and a reduction or distortion of fruit. Infected plants may need to be destroyed to prevent the virus spreading. Pests Passionflower is also susceptible to pests, including aphid, whitefly, red mite spider and mealybug. This is particularly true if you are growing your plant in a greenhouse, as these pests favour a warm environment. “Passion flowers are prone to spider mites and mealy bugs,” explains Myles. “These are best treated by spraying or hosing down your plants with water daily, above and below the leaves.” Check your passion flower regularly for signs of infestation. Mould & Fungus As with many plants, you should also watch out for any signs of a fungal infection – signs can include black patches and visible mould. Help to avoid this by ensuring the plant is in full sunlight, and that you only water the soil at the base of the plant, not the leaves. Other than these, the most common problems that affect passion flower are wilting, wind scorch and blackened leaves, which may be caused by harsh weather or winter frost. References 1. Passiflora caerulea. (n.d.). Kew Royal Botanic Gardens. Retrieved March 22, 2023, from https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:321949-2 2. Passiflora incarnata. (n.d.). Missouri Botanical Garden. Retrieved March 22, 2023, from https://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?kempercode=q280 3. Passiflora incarnata. (n.d.-b). Center for Aquatic and Invasive Plants: University of Florida. Retrieved March 22, 2023, from https://plants.ifas.ufl.edu/plant-directory/passiflora-incarnata/
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Mastering Bougainvillea Growing - The South American Evergreen Climber
IN THIS GUIDE Overview Common Varieties Habitat & Growing Conditions Plant Care Support Pruning Common Problems Overwintering References If you’re looking to add an explosion of colour to your greenhouse or garden borders during summer, tropical Bougainvillea, with its bright green leaves and vivid magenta bracts, might just be the perfect choice. This South American evergreen climber favours a warm climate and will struggle to survive frost, so if growing outside in the UK, it must be brought inside during winter. Growing it in a pot or container will allow you sufficient control of its environment for it to flourish. Alternatively, a heated greenhouse provides the ideal environment for a Bougainvillea to thrive, being warm and with direct sunlight protected by glass. You could also grow the plant exclusively inside, in a warm conservatory or on a sunny windowsill, and attach it to a trellis for support as it climbs. Whilst it may not be the easiest plant to grow – with the right knowledge, there’s no reason your home or garden can’t be filled with beautiful Bougainvillea blooms every summer. Overview Botanical Name Bougainvillea Plant Type Climber Native Area Americas Hardiness Rating H3 Foliage Evergreen climber Flowers Bright showy flowers and bracts When To Sow June, July, August, September Flowering Months June, July, August, September When To Prune February, March Bougainvillea is a tropical vine that is native to Central and South America, including Peru, Brazil and Argentina, and is thought to have been first introduced to Europe in the early 19th Century.1 These days, it is grown in many warm climates around the world, from Florida to Greece. Bougainvillea is characterised by bright green foliage, with curved, black-tipped thorns and tiny white flowers found at the centre of the colourful blooms. These sought-after vivid blooms are actually paper-thin bracts (coloured leaves). Providing it has plenty of sunlight, the plant will re-flower several times during a UK summer, dropping its bracts each time. Bracts are most commonly found in shades of pink, magenta and purple, although many other colours also exist, including white, yellow, orange, red, and two-toned varieties. Common Varieties Larger varieties of Bougainvillea can reach up to 10m tall with support and 10m wide if grown as a groundcover. There are also dwarf cultivars that are unlikely to top 1m tall or wide. Of the 18 species of Bougainvillea that exist, only a couple are commonly cultivated and grown in the UK. A good one to look for is ‘Barbara Karst’, which has bright magenta bracts and is one of the hardiest varieties, most likely to succeed in a UK climate. Low-growing B. glabra and B. buttiana (a hybrid) are two of the best choices for hanging baskets and containers. Habitat & Growing Conditions Bougainvillea’s natural habitat is the tropical and sub-tropical, coastal areas of Central and South America. In these environments, the plant receives lots of sunlight, and benefits from high temperatures and humidity. In warmer climates, Bougainvillea will flower practically year-round, not just in summer. Plant Care Bougainvillea should be planted, or, if necessary, re-potted, in early spring. We recommend planting in a container, with plenty of room for the root system. Soil Requirements Bougainvillea grows in nutrient-rich soil, in areas with plenty of space to accommodate its root system (which can be quite significant on a larger variety). It prefers a drier soil with good drainage, as too much water can cause the roots to rot, and it does well in periods of drought. As the plant is native to coastal areas, it also has a higher-than-average tolerance to salt. Bougainvillea favours a slightly acidic soil and needs plenty of nutrients. Use a well-rotted compost and a loam-based fertiliser, such as John Innes. Sunlight The plant requires full sunlight (at least 6 hours a day), although it should be protected by glass from direct light during summer. It also needs heat – you should place it outside only in late spring and summer. Otherwise, keep it indoors or in a greenhouse, ensuring the temperature of its surroundings stays above 10°C. Watering Bougainvillea does not have a high water requirement. You should water it regularly whilst it’s growing (when the soil starts to feel dry), but once matured, a thorough watering every 2-3 weeks during spring and summer should be enough. Use pH-neutral rainwater and add a high-potassium liquid plant feed to encourage blooming, if necessary. Be careful not to over-water, as this will cause the plant to replace flowers with an abundance of green leaves and can also lead to root rot. Once the flowering period is over, around September, the plant will go into winter dormancy, and should only be watered very occasionally – although refrain from leaving it completely dried out for a long period of time, and water immediately if it starts to wilt. Support In order for a potted Bougainvillea to thrive indoors, you will need to tie it to a trellis, or another support system. Training Bougainvillea On A Trellis If you have planted your young Bougainvillea in a container, and you want it to grow upwards, you need to provide it with the support of a trellis. This should be inserted into the soil when you pot your Bougainvillea, to avoid damage to the roots at a later date. Place the trellis behind the growing plant and use plant ties to loosely tie the vines to it, approximately every 30cm. Keep adding more ties as the plant grows – make sure you tie them tightly enough to secure the weighty branches. When it reaches maturity, it will be ‘trained’ and will not require further ties, unless you wish to change the direction of growth. Pruning Pruning your Bougainvillea is essential to encourage new growth and flowering. The best time to prune is in late winter / early spring – the end of February is usually about right. The aim is to prune before the new year’s growth begins in March, as this will ensure your plant is in the best possible position to flower. Take this opportunity to re-shape your Bougainvillea, removing any damaged or wayward branches, and setting it up for how you want it to grow. Limit overall pruning to a maximum of 50% of the plant, and always wear gardening gloves when pruning, to protect yourself from the thorns. As well as this hard pruning prior to the growing season, you can also undertake a lighter pruning after each blooming in summer. This will encourage a second, or even third wave of bracts before the season is out. Common Problems The most common problem that occurs with Bougainvillea is wilting and leaf drop, as a result of it being exposed to too low temperatures. Prevent this by bringing the plant inside during the winter months, and ensuring the surrounding temperature doesn’t drop below 10°C. Other than that, Bougainvillea is generally fairly hardy – it can survive with limited water, and there are not many diseases that are specific to it. It may, however, succumb to some general pests, such as whitefly, aphid and red spider mite. Whitefly can be a particular concern as they favour a warm climate, such as the one you’ll be providing for your Bougainvillea. Visible signs of whitefly include the tiny white bugs themselves, the sticky honeydew substance they produce, and the black mould which develops as a result of the honeydew. An infestation can be controlled biologically, by introducing Encarsia Formosa (parasitoid wasps) to the environment, or by using an organic insecticide, as Master Horticulturist Colin Skelly explains in more detail: “Biological controls are best introduced at planned intervals rather than as a response to infestation. “It will take time for the parasitic insect to build up in response to the increased population of whitefly. “Infestations are best controlled with organic insecticide with biological controls introduced once the whitefly is under control. “Definitely don’t spray after you have introduced parasitic insects as this will kill both the hunter and the hunted.” Overwintering Bougainvillea favours a warm climate and does not do well in temperatures below freezing (or temperatures under 10°C). Therefore, if left outside unprotected, it may not survive a UK winter – or at least, it could suffer significant damage. To protect a Bougainvillea from frost, you should ideally grow it in a container, that you can move inside in autumn, before the first frost of the year. Try to find your plant a nice spot in a sunny conservatory or porch, where it can remain until winter is over. If you’re growing Bougainvillea in your garden, there are still steps you can take to try to protect it from frost. Monitor the weather forecast, and if a frost is expected, cover your Bougainvillea with a blanket or plastic sheet. Use stakes to make sure it doesn’t touch the plant, but rather hangs over it like a protective tent. Remove the cover once the temperature rises. References 1. Bougainvillea species. (n.d.). Oxford University Plants. Retrieved March 13, 2023, from https://herbaria.plants.ox.ac.uk/bol/plants400/Profiles/ab/Bougainvillea
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How To Grow Amaryllis Plant - The Wintertime Favourite Also Known As Hippeastrum
IN THIS GUIDE Overview Common Varieties Habitat & Growing Conditions Hippeastrum Care Common Problems References The Amaryllis plant, often considered a type of lily, is a wintertime favourite. Correctly called Hippeastrum, this houseplant bears colourful blooms in the form of a bell with its six tapered petals giving it a star shape. They come in a range of striking and brilliant hues. Some are two-toned, others have a central blaze, or even delicate veining. Eye-catching, charming, dazzling – all these adjectives and more can truthfully be applied to one or another species or cultivar of this ever-popular indoor plant. The amaryllis, a bulbous perennial, brightens up many homes during the festive season as it has the felicitous facility of flowering right around Christmas. The bulb can be induced into dormancy at any time after blooming. Similarly, it can also be ‘timed’ to bear flowers at the most suitable period by re-planting the bulb six to eight weeks before you want it to flower. Nurseries have long been selling amaryllis cultivars during November with the bulbs primed or ‘forced’ to flower in late December. Overview Botanical Name Hippeastrum Common Name(s) Amaryllis Plant Type Bulb / Perennial Flower Native Area South America Hardiness Rating H1-H2 Foliage Slightly fleshy strap leaves Flowers Large, funnel-shaped blooms in various hues When To Sow January, October, November, December Flowering Months January, February, March, April, December Native to South America, Hippeastrum species have been cultivated, crossed, and bred for a few centuries to create an amazing array of flowers.1 Most amaryllis plants are easy to grow and maintain indoors which is yet another reason for their popularity. If the bulb is treated with care, it will produce flowers for many years. Common Varieties To begin with, Hippeastrum is a genus with over 90 species to which one must add the 600-plus hybrids and cultivars of amaryllis that derive from Hippeastrum species.2 We outline a mere handful of the notable ones below – Hippeastrum papilio is a Brazilian species whose flowers are of an odd yet riveting colour combination. The outer parts of the tepals are a varying but light shade of green while the inner part ranges from carmine to maroon, often with striations. Bearing distinctly trumpet-shaped flowers of a soft vermilion hue, Hippeastrum miniatum is a decorative enough species so as to contend with the showiest of cultivars. Peruvian-Bolivian native Hippeastrum pardinum bears flowers which are star-shaped and open, with the reddish freckles and spots on yellowish tepals making it one of the most beguiling blooms. H. puniceum Hippeastrum puniceum commonly called Barbados Lily also has open, star-shaped flowers; their colour ranges from pale orange to vermilion, with a central splash of yellow to make for the prettiest of flowers. Giving the Barbados Lily species heavy competition is the ‘Orange Sovereign‘ cultivar; a variety whose flowers are of a single solid hue. The simplicity of the colour scheme and the deep flame colour combine to make for an eye-catching flower. ‘Orange Sovereign’ ‘The Red Lion’ has flowers with a rounded contour and its tepals are curved and mounded, and of a crimson hue. It is a very luxurious cultivar. ‘Minerva’, not dissimilar in shape to ‘Red Lion’, is of a more sedate shade of red but, unlike ‘Red Lion’, it has a blaze and lengthwise bands of white, making it one of the most charming cultivars. ‘Candy Floss’ ‘Candy Floss‘, true to its name, is of a candy floss pink except that this well-balanced flower’s colour comprises of many hues and tints of pink in streaks, striations, and veins. Plump, well-rounded tepals bearing red dots and spots and daubs on a white background make the ‘Flamenco Queen‘ appear voluptuous yet shy and vulnerable. The ‘White Peacock‘ – an obvious contradiction in terms – though a ‘double flower,’ has three sets of tepals. Pure white, it conveys both restraint and elegance. ‘White Peacock’ The ‘Viridi Rascal‘ is also white but this single flower has vivid red striations and red edging on its tepals combined with gentle ridging, with the overall effect one of delicate beauty. The vast range of the species and cultivars of this delightful plant means that regardless of your taste, there is a feast for the eyes and a treat for the senses for every flower enthusiast. Habitat & Growing Conditions Hippeastrum occurs in nature mainly in the tropical and sub-tropical regions of South America. Different species prefer their own place in the sun – or the shade! That is, Hippeastrum species range in preference from full sun to mostly shade. A few like damp soil and others occur in dry earth with most species preferring areas with regular rainfall but good soil drainage. Hardiness As a garden plant, amaryllis cultivars are hardy in USDA Zones 8 through 11 (RHS Zones H1C – H5) though some, like Hippeastrum x johnsonii, are hardy down to USDA Zone 5 (RHS Zone H7). A cultivar may perish during a freeze or a frost – most cultivars do best in screened sun or morning sun. The most important requirement is that the soil must drain well and not retain any water. You can transfer your garden amaryllis indoors for the winter by simply removing the bulb from its bed at the beginning of autumn and inducing dormancy by keeping it in a cool, dark place without water or fertiliser for two to three weeks and then re-planting it in a pot. Hippeastrum Care Though Hippeastrum makes a lovely addition to any garden, our guide treats it as a houseplant. If you plant a cultivar outdoors simply adapt the guidelines accordingly. Use a largeish flower-pot because amaryllis plants are, to some or another degree, top-heavy. Aim for a room temperature of 20-21°C and place the pot where it will get four to six hours of sun daily. Soil Requirements The best soil pH range for amaryllis is between 6 and 7. Master Horticulturist Colin Skelly advises: “For many potted bulbs I usually use a peat-free John Innes no.2 growing medium (the name of the ‘recipe’ rather than the producer – it is sold by different companies).” “This has added grit for drainage but also good nutrient content and moisture retention – perfect for most bulbs in pots.” The soil should be composed of about one-third perlite or gravel and two-thirds of some combination of peat moss, loam, or compost. Plant the bulb so that about one-third of it is above the soil; it is imperative that the nose not be covered by soil. It is just as imperative that the soil drains properly. Watering & Feeding Upon planting the bulb immediately water it thoroughly and thereafter water it lightly or moderately every few days. As leaves and stalks sprout, watering should gradually be increased in amount and frequency, and fertilise every two months with a 10-10-10 houseplant fertiliser keeping in mind that it is worse to over-fertilise amaryllis than to under-fertilise it. A good rule of thumb is to water when the topsoil is dry to the touch, to water once or twice a week, and to try to keep the soil just moist but never wet. Plant the bulb in October to enjoy blooms during the holiday season. Common Problems Bulb Rot Hippeastrum is vulnerable to various diseases – where bulb rot is concerned, prevention is better than cure. Assuming healthy bulbs, the only causes for this disease are overwatering, waterlogged soil, and poor drainage. Therefore, if you make sure not to overwater and also ensure that your soil drains well, you eliminate bulb rot. Pests Pests like mealybugs, aphids, mites, grasshoppers, and bulb maggots can attack the plant with mealybugs being the most common houseplant pest. Grasshoppers lay egg pods beside amaryllis bulbs. These hatch in spring and cover the plant. Here too, prevention is the better option. Keep checking your plants for these pests and if you observe them, dislodge the smaller pests with blasts of water and remove grasshoppers by hand. If the problem persists, use an insecticidal soap solution. Dilute to specifications and spray on the plant. If your mealybug-infested plant is in the garden, you can release beneficial insects like ladybugs – these prey upon mealybugs. Aphids are perhaps the most dangerous of pests because they breed rapidly and in numbers, and cause irreversible harm to the plant. “If you spot an aphid infestation, use an insecticidal soap and/or blast off with water,” adds Colin. Bulb mites are more difficult to spot for obvious reasons. A side benefit of annual removal of the bulb from the soil and later re-planting is that you can inspect the bulb for mites (and other pests or disease, bruising, and onset of rot). References 1. Hippeastrum aviflorum. (n.d.). Kew Royal Botanic Gardens. Retrieved March 9, 2023, from https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:993998-1 2. Hippeastrum Herb. (n.d.). Global Biodiversity Information Facility. Retrieved March 9, 2023, from https://www.gbif.org/species/144107351
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These 6 Dry-Tolerant Ferns Provide Vertical Accents And Fine Texture In Shade Planting
IN THIS GUIDE 1) Crested Scaly Male Fern 2) Soft Shield Fern 3) Common Polypody Fern 4) Hart’s Tongue Fern 5) Eared Lady Fern 6) Slender Crested Male Fern Dry Loving Ferns With Amusing Names Ferns & Eco-Friendly Pest Control References Ferns are plants which are loved by gardeners everywhere, thanks to their hardiness and their ability to bring colour and beauty to any shady spot in the garden. Fossils testify to the fact their ancestry stretches back 360 million years – and yet they have changed very little, if at all, since their initial appearance on this planet.1 These outdoor – and indoor – plants are tough in the sense they’re not prone to disease, brush off pests and don’t need much looking after (although there are potential exceptions – see below). In fact, all that’s really required is that you cut away the dry fronds to allow the new ones to get going. There are basically two different types of fern – evergreen (which retain their leaves all year round, unless there proves to be an exceptionally cold winter) and deciduous ferns which uncurl and announce their presence in our gardens in spring. And not all ferns like dry conditions either; some ferns favour moist growing conditions, while others are more at home in practically boggy environments. Of those that do tolerate dry conditions, they tend to prefer dappled sunlight via the leaves of deciduous trees, rather than being completely exposed to the intense mid-day heat. “All ferns need moisture in order to reproduce but some, like those in this article, have evolved to cope with seasonally dry conditions,” says Master Horticulturist Colin Skelly. “I love dry-tolerant ferns because they can be used in shade that is moist and provides vertical accents and fine texture in shade planting.” Others are fine nestling in the ground at the bottom of a north-facing wall, while all will appreciate a little bone meal and leaf mould. They will also require a little watering in their first season, along with some mulch, at least until they’re past the initial growing phase. “It is important to try and choose plants from the garden centre that are able to tolerate dry conditions and will be more adaptable to the challenges of climate change,” shares Wes Shaw, a Garden Designer. In this article, we are concentrating only on ferns which prefer the dry spots in your garden – the areas other plants have, or will, shun. And here is a list of our particular favourites: 1) Crested Scaly Male Fern BOTANICAL NAME: Dryopteris affinis ‘Cristata’ HARDINESS RATING: H5 FOLIAGE: SEMI-EVERGREEN UK NATIVE / RHS AWARD OF GARDEN MERIT ‘Cristata’, meaning ‘crested’, this graceful king fern is capable of growing in both dry and moist soil, although it does best in the former. This fern is tall when fully-growing, reaching up to three-foot at its highest. The fronds should be cut back in the middle of winter. When flourishing though, appropriately enough, the crests on this fern are dark green and heavy, forcing the ends of the fronds to bend. This, in turn, makes the fronds appear to curtsey. 2) Soft Shield Fern BOTANICAL NAME: Polystichum setiferum ‘Pulcherrimum Bevis’ HARDINESS RATING: H6 FOLIAGE: EVERGREEN RHS AWARD OF GARDEN MERIT A beautiful plant reminiscent of lace, the Soft Shield Fern’s fronds swirl upwards before tapering to a point around one metre from the ground. Some gardeners say the shape reminds them of a badminton shuttlecock which is green with brown bristles. An elegant evergreen, it flourishes under dappled light but should be given lots of space to allow it to expand into a large and luxuriant addition to your garden. This is an expensive fern to buy but can be found growing wild in Devon where it was discovered last century by a hedge-layer of the name Bevis.2 3) Common Polypody Fern BOTANICAL NAME: Polypodium vulgare HARDINESS RATING: H7 FOLIAGE: EVERGREEN UK NATIVE A hardy evergreen fern, whose rather plain name, belies its pretty foliage. The fronds resemble a ladder with what appears to be pimples on the underside. It will reach a height of around 30cm and can certainly flourish unless you cut it back. Then again, it makes a pretty covering for dry soil underneath trees. 4) Hart’s Tongue Fern BOTANICAL NAME: Asplenium scolopendrium HARDINESS RATING: H6 FOLIAGE: EVERGREEN RHS AWARD OF GARDEN MERIT A tough and shiny fern whose strap-like fronds have a spikey appearance, this interesting-looking evergreen has the capacity to withstand even a drought when planted in alkaline-heavy soil. It flourishes under trees and especially in forests where it grows wild – it will even grow out from a north-facing wall. Another fern which practically looks after itself, Hart’s Tongue only requires a little mulch now and again as well as a little snipping and tidying when spring comes around. It can grow to a height of up to 60cm. There are variations to the leaves such as ‘Marginata’ with its crinkly, serrated edges and ‘Cristatum’ with pretty ruffles at the tips of its fronds. 5) Eared Lady Fern BOTANICAL NAME: Athyrium otophorum ‘Okanum’ HARDINESS RATING: H4 FOLIAGE: DECIDUOUS RHS AWARD OF GARDEN MERIT Also known as Auriculate Lady Fern, this plant enjoys a well-known love of dry soil. It is a colourful fern with very light green, almost yellow triangular leaves and a prominent red/purple stripe down the centre with ribbed veins. Originating from Japan, it can grow to around 80cm at its tallest. It suits most shaded locations. You’ll see it in spring, summer and autumn – before it takes a break for winter. Unlike a lot of ferns, this variety won’t spread. 6) Slender Crested Male Fern BOTANICAL NAME: Dryopteris filix-mas ‘Linearis Polydactyla’ HARDINESS RATING: H7 FOLIAGE: DECIDUOUS RHS AWARD OF GARDEN MERIT Not your typical male fern, this rather delicate plant has long, arching but rather delicate fronds – to the extent it has an almost skeletal appearance. It is large though and will grow to a height of 60cm. A delightfully-named fern – which also goes by the term ‘Many-Fingered Male Fern’ – it looks particularly good beside thicker and bolder plants. Dry Loving Ferns With Amusing Names It is not just the varied textures and fascinating foliage shapes of ferns which have been delighting gardeners all these centuries. No, their often unpronounceable and amusingly descriptive names play a part too. Names, such as congestum, for instance, to describe a ‘busy’ plant. Then there is the fimbriatum (with its small fringe), or the crinkled lettuce-like leaves of the frizelliae, the arrow-like leaves of the sagittate and the scallop-shaped crenatum. Ferns & Eco-Friendly Pest Control Although ferns aren’t typically known for being bothered with pests, there are a few garden culprits to keep an eye out for with particular ferns. Slugs, snails, and caterpillars often have a fancy for the strappy fronds of the Harts Tongue fern, finding them highly edible. Crosiers too, can prove an interesting snack for garden herbivores. One proven method to deter them is to add bark and gravel to your mulch since this can often prevent them from reaching the ferns in the first place. You could also attempt to distract them from the fern by putting down beer traps and citrus peel. References 1. Fern fossils. (2013, December 19). Earth Sciences Museum. Retrieved March 15, 2023, from https://uwaterloo.ca/earth-sciences-museum/resources/fern-fossils 2. The Bulletin of the British Pteridological Society. (n.d.). British Pteridological Society. Retrieved March 15, 2023, from https://ebps.org.uk/wp-content/uploads/2014/06/Bulletin2010pt1_Final2_BW_A4.pdf
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