Growing
Campsis ‘Trumpet Vine’ Propagation, Pruning And Training Rules To Follow
IN THIS GUIDE Overview How To Grow Trumpet Vines Pruning & Training Plant Care Common Issues References With anywhere from one to a handful of words, a name can encapsulate the exact features and qualities that make a plant unique; that stand it out from the crowd. And when you look at Campsis radicans – most commonly known as the ‘Trumpet Vine’ – it’s easy to see why we think the plant belongs firmly in this hallowed category of perfectly named plants. An elongated throat holds the petals far away from the stem where they open proudly, resembling the brass bell that distinguishes the end of a trumpet. Thanks to its stunning aesthetic qualities – we’re talking about the intriguing shape and the bold colours – the trumpet vine has become a popular addition to British gardens since it was found by colonists in Virginia and brought home to Blighty.1 Overview Botanical Name Campsis Common Name(s) Trumpet Vines Plant Type Climbers & Vines Native Area Americas Hardiness Rating H4 Foliage Deciduous Flowers Trumpet-shaped When To Sow January, February, March, November, December Flowering Months July, August, September When To Prune March This plant is in the family Bignoniaceae, and as we just alluded to, is native to America.2 Its hardiness has allowed it to establish itself in many places around the world. Being a vine, Campsis radicans grow enthusiastically, and puts out numerous tendrils that do their best to attach themselves to any surface in the vicinity. Because of this wild growth, trumpet vine is considered to be invasive by some gardeners and authorities.3 With this in mind, we recommend remaining vigilant if you decide to grow it. How To Grow Trumpet Vines Where To Grow As a vine, Campsis will grow well against a wall or structure, like a trellis. If you’re concerned about your plant getting unruly you may find more peace of mind growing in a container, where you can be sure that you can keep things contained if need be. C. × tagliabuana ‘Madame Galen’ Regardless of your decision whether to plant in the ground or a container, find a spot that’s warm and sunny. This plant requires shelter from the elements, especially cold wind, and strong sunlight is needed to help ripen its stems into wood. Sowing From Seed It’s possible to grow trumpet vine from seed, although this is not considered the optimal method. Choose potting compost, or mix organic matter with your garden soil – then fill a container and sprinkle the seeds on top. Check the seed packet for information on how much space to leave between them as this can vary between types. Add another thin layer of soil on top of the seeds, and then water well. For best results, leave your trumpet vine container in a place that will get good amounts of light and heat – a windowsill or greenhouse is usually a good bet. You can cover the pot with a clear plastic bag, making sure to put a stake in the soil to keep the plastic away from the surface. This will trap heat and moisture, creating conditions that are conducive to germination. Propagating From Cuttings To propagate a trumpet vine, simply trim 7.5-10cm from the suckers or shoots of an existing plant. Plant the cutting and keep it moist, and you should see new growth within a few weeks. Nurture the plant until it’s strong enough to plant outside, then prepare to plant out. Pruning & Training As a keen vine, Campsis will demand more of your time than some other plants. In the early years this involves training your plant, to encourage the development of a solid framework that will be the basis for future growth. Once your plant is established, attention turns toward keeping it in check with a thorough pruning regime. Then, once a plant is mature, you can renovate it to promote new shoots. Here’s a little information on each – Trumpet Vine Training By taking the time to train your vine in the early months, you can lay the groundwork for manageable and aesthetically pleasing coverage. Choosing the right support and encouraging your plant to grow as desired leaves more space, achieves more balanced growth, and makes it easier to care for going forward. The first step involves choosing a support; this can include wires, trellises, screens, and others. “When considering support for a climber, remember that you might have it for some time,” says Master Horticulturist Colin Skelly. “I tend to prefer wires over timber trellises because timber will not last as long and is tight to walls, whereas wires create more space between the wall and the climber. “Sometimes though, timber is the right choice for the job aesthetically.” Remember when planting out that you need to leave space between your plant and the support (typically 25-50cm) to prevent the support from blocking rain from reaching the plant. If you’re growing trumpet vine from seed, a pyramid frame of short canes is a good starting point. Manually wrap the vines around the canes, tying them on to keep them separate. Remember that you’ll need to untie them to move them to the permanent structure when they’re ready, so leave space and don’t tie knots too tight. Instructions for the next step vary between the type of support chosen, but the general idea is to train your vines onto the structure in a way that promotes neat and tidy growth. Where necessary make sure the structure is firmly attached to a wall, as the weight of a mature plant may pull it down otherwise. Remove weak shoots during the training process to help your plant stay as strong as possible. Pruning Guidelines The goal of pruning is to keep a mature plant in optimal condition, both in terms of health and appearance. By investing time and effort here you can help your trumpet vine to remain fully resplendent. At the end of each growing season cut back side shoots so that they only reach a couple of buds beyond the main stem. Get rid of weak growth, and if any stems are damaged, trim them back close to the base of the plant. Renovating Established Vines If your trumpet vine is looking a little old and dishevelled, you can do a ‘hard reset’, as it were. To do this, trim all of its shoots back to about 30cm in height, and retrain as you would with a new plant. Plant Care Watering Trumpet vines aren’t overly thirsty compared to some others, but will benefit from being watered in dry periods. This is true whether your plant is newly-established or well-established, and whether it’s growing in the ground or a container. Fertilising If your trumpet vine is growing in the ground, add fish, blood, and bone fertiliser in spring. Check the packet for details on the amount to use, as this will vary based on the size of your plant. In a container, traditional liquid plant feed should do the trick. Generally, trumpet vine doesn’t require too much feeding unless the soil is particularly low in nutrients. Feeding each year will encourage stronger growth, nonetheless. Common Issues There’s not much that’ll get in the way of this energetic plant and its ambition to grow as far and wide as possible. Here’s information on a couple of things that could disturb healthy growth, just in case – Bud Drop This refers to a phenomenon where buds drop off of a plant before opening, and can indicate that your trumpet vine is in a poor location. One thing to check is soil acidity – this plant can tolerate a wide range from mildly acidic through to mildly alkaline – but do check for any deviation beyond that range. If soil acidity is ok but your buds are still dropping, it may be the case that the soil is too wet. Check for overly-moist, potentially boggy soil; if you find it, add organic matter or leaf clippings to shift the moisture ratio to something more favourable. If you’re still encountering issues, check whether the vines are growing too tangled. If so, try to tease them apart and consider pruning back some of the weaker ones. Pests Aphids, scale insects, and mealybugs are prone to visit trumpet vine as a source of food. Sadly these visitors cause damage to any plant – leaving blemishes, brown spots, and potentially even killing off sections off if left unchecked. Keep vigilant, and look for any bugs that are visible to the naked eye. If you find any, remove by hand and check back to make sure they don’t return. Should they return, pesticide is often the next course of action – different products are recommended depending on the type of insect and the scale of the infestation. References 1. Campsis radicans. (n.d.). Global Biodiversity Information Facility. Retrieved March 13, 2023, from https://www.gbif.org/species/144104315 2. Bignoniaceae. (1999, July 23). Encyclopedia Britannica. Retrieved March 13, 2023, from https://www.britannica.com/plant/Bignoniaceae 3. Trumpet creeper: Campsis radicans. (n.d.). Invasive Plant Atlas of the United States. Retrieved March 13, 2023, from https://www.invasiveplantatlas.org/subject.html?sub=5258
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Nasturtiums Are Resilient Low-Care Climbers: Here's How You Can Grow Them Each Year
IN THIS GUIDE Overview Habitat & Growing Conditions Planting How To Grow Nasturtiums Plant Care Pruning Common Problems References Tropaeolum, commonly called Nasturtium, is a genus of climbing, sometimes creeping, plants that have fantastic ornamental value in terms of their heights and spreads, foliage and flowers. These rather unusual plants typically have a very long blooming season, and their flowers come in an astonishing variety of colours from icy blue to blazing red. “I grow nasturtiums every year,” says Gardener Hannah Reid. “I love nasturtiums for their beautiful flowers and leaves. An additional bonus is that the entire plant is edible – flowers, foliage and seeds, which are amazing pickled!” It is not to be confused with Genus Nasturtium which encompasses Cress species. Nasturtiums are unusual plants on several counts: First, most of them are resilient, if not always strong, climbers though a few have a bushy, spreading habit. Second, their foliage is both uncommon and attractive. Third, their brilliant flowers are even more attractive; what’s more, they bloom for months on end. Fourth, they are very low-care plants. Fifth, they are effective companion plants to a whole host of edible plants. Taxonomically there is a connection to the abovementioned Cress because both Genus Tropaeolum (‘Nasturtium’) and Genus Nasturtium (Cress) fall under Order Brassicales, many of whose members are edible and which have a tangy, peppery, or pungent flavour, with Mustard probably being the ‘Head of the Family’.1 As it happens, Nasturtium flowers and leaves are edible and lend a piquant zing to salads and even soups. Out of Rocket? Not a problem if you have a Nasturtium in the garden. Overview Botanical Name Tropaeolum majus Common Name(s) Nasturtium Plant Type Annual Flower / Climber Native Area South & Central America Hardiness Rating H3 Foliage Deciduous Flowers Commonly red, yellow or orange When To Sow March, April, May Flowering Months July, August, September, October Though Nasturtiums are deciduous perennials, in most regions of the United Kingdom they are half-hardy and are grown as annuals. However, along the south-western coast and a few other regions, several varieties can be grown as the perennials that they are (though a few varieties, such as T. tuberosum and T. speciosum, can be grown as perennials in almost all regions of the UK). If you are lucky enough to call a relatively balmy region home, you can bring great joy to your garden by growing arguably the most ornamental of all climbers. T. majus To begin with, the foliage is of a mellow sea-green colour. The leaves are decorative in their own right, being either lobed, often deeply, or rounded and shield-shaped. The showy flowers come in hues of yellow, orange and red, but a few are in shades of blue and purple and some are also bi-coloured or variegated. To top it all off, Nasturtiums bloom for months on end, many varieties are fragrant, and the flowers attract butterflies and hummingbirds! Habitat & Growing Conditions Tropaeolum grow in the wild from south-eastern Mexico and Guatemala in the north to the tip of Patagonia in the south, excluding Brazil. Some species grow at altitude in the alpine regions of the Andes while others grow in lowland coastal areas; Chile is a particular centre of species diversity.2 T. majus ‘Empress of India’ What is common to all of them is that they are indifferent to soil – as they grow in soils ranging from average down to what can only be typically considered very poor. They are usually found growing in full sun; though their water needs are low they do best in moist soil. The vast majority of Nasturtium species are frost-tender and are hardy (only) to Zone H3. A few species, though, are frost-hardy down to Zone H5. T. speciosum Planting Most Nasturtiums are climbers that attain heights of about 3m. A few, such as T. speciosum and T. peregrinum, can reach heights of up to 4m. An overgrown Nasturtium climber along the wall of a house will impart a charming, country-cottage effect to your urban dwelling. They will produce the same countryside charm when they climb up and wash over boundary walls and fences with next to no training. The shorter, more delicate, Nasturtiums, for example T. azureum, are ideal to plant beside summer-houses, especially when the walls are of latticework – then a few flowers and leaves will ‘peek’ inside. Some Nasturtiums have a spreading, bushy habit. Examples include T. majus ‘Empress of India’ and T. majus ‘Chameleon’. If grown in large planters these species will add great colour and produce a delightful billowing effect by the patio or on the porch. They can actually be used to create borders as well. How To Grow Nasturtiums Nasturtium seeds of the spreading, trailing varieties, are widely available at nurseries and online stores. In addition, seeds of the more popular climbers, for example T. speciosum, are just as freely found. Some, such as T. majus ‘Chameleon’, are much harder to find. Because species of this genus do not take well at all to transplanting, only a few varieties, such as the bushy, spreading varieties, are available as plants in containers from a limited number of garden centres. If you already have a Nasturtium, you may be able to get new Nasturtiums for yourself and your friends. Some species self-seed very reliably. You can often simply let the flowers wither and then harvest the seed pods. Plant Care Most, if not all, Tropaeolum varieties can be grown reliably from (the rather large) seeds. One may as well add that they will just as reliably start to wilt and wither if transplanted. Therefore, do not start these plants in pots for later transplanting though you may very much grow and keep short and spreading varieties in planters. Soil Requirements Besides being very transplanation-averse, these plants have yet another quirk. They do best in poor soil! The richer the soil, the more foliage they will produce at the expense of flowers. A mix of gravel, chalk, and sand with but a sprinkling of humus or manure mixed in will be perfect though any old soil will do. Soil pH hovering around neutral is ideal though any pH from moderately acidic to slightly alkaline will do fine for most Tropaeolum varieties. The one non-negotiable is that soil should drain very well. Watering These plants should be watered about twice a week, be it from the rains or the hosepipe. When the soil dries out, it is time to water them. Younger plants need more regular watering than established outdoor ones. Feeding Avoid fertilising Nasturtiums of any kind. Nitrogen-high fertiliser especially should be avoided because it will spur growth of foliage on an already leafy plant; in turn, this will negatively affect the number and size of blooms. T. majus ‘Jewel Cherry Rose’ Indeed, even a balanced fertiliser would not be a smart idea for Nasturtiums under most circumstances. Overwintering If you have grown a Nasturtium as a perennial in the UK, then, if it is of a type that is dormant in winter and is not frost-hardy (the majority of varieties), soon after the leaves have shed in autumn, you should spread a layer of leaf mulch on the soil above the root system. Remove it a couple of weeks after the last frost of winter. Pruning In general Nasturtiums do not need to be pruned as they are deciduous plants (assuming you can grow them as perennials and not as annuals). “Nasturtiums are so vigorous that, unless you are happy for them to be rampant, you will need to cut back the stems,” shares Horticultural Consultant Colin Skelly. “Just cut back stems to just above a leaf and your Nasturtium will happily keep growing around whichever area you want clear.” In general, the bushy spreading varieties may be cut back soon after the flowering season is over. Climbing varieties can be deadheaded to encourage fresh blooms. T. majus ‘Black Velvet’ Don’t get caught out by the flowering season and dormancy season of your Nasturtium variety; keep in mind that T. azureum, T austropurpureum, and T. tricolor are all dormant during the summer and bloom in winter and spring. Common Problems Tropaeolum is an inherently healthy genus and is known to stay free of disease but the different varieties have varying susceptibilities to pests. In general, the shorter Chilean climbers are the most robust while T. majus and its varieties are the least robust. Both T. speciosum and T. peregrinum may be attacked by flea beetles and caterpillars with the former also a target for blackfly and the latter for aphids. T. majus and its cultivars are susceptible to blackfly, flea beetles, and caterpillars, in addition to which a lesser threat is posed by slugs. References 1. Nasturtium (water-cress). (n.d.). Native Plant Trust: Go Botany. Retrieved March 21, 2023, from https://gobotany.nativeplanttrust.org/genus/nasturtium/ 2. Tropaeolum majus. (n.d.). Kew Royal Botanic Gardens. Retrieved March 21, 2023, from https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:310974-2
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Star Jasmine Is An Attractive Woody Climbing Plant - Here’s Why It Can Be Difficult To Grow
IN THIS GUIDE Overview Why Grow Star Jasmine? Where To Grow How To Grow Star Jasmine Ongoing Plant Care References Commonly grown as an ornamental garden plant in milder areas, and as a houseplant, there are a number of reasons to grow star jasmine, wherever you live. While Star Jasmine might not be the easiest plant to grow, it certainly can be a rewarding one to feature in your home or garden. An attractive woody climbing plant, it is particularly prized for its evergreen foliage and its wonderfully scented flowers. In the UK, Star Jasmine can be grown as a climber in a sheltered and sunny garden in the south. Further north, it can be grown undercover in a greenhouse or polytunnel, or in a container indoors. Overview Botanical Name Trachelospermum jasminoides Common Name(s) Star Jasmine Plant Type Climbers Native Area Japan, Korea, Southern China & Vietnam Hardiness Rating H4 Foliage Glossy, evergreen, ovate leaves Flowers Fragrant white flowers When To Sow April to May or September to October Flowering Months June to August When To Prune March to April or August Star Jasmine is a flowering plant in the Apocynaceae family.1 It is native to Japan, Korea, southern China and Vietnam, but is now commonly grown in many gardens and homes around the world.2 Scented white flowers appear from mid to late summer, and the dark green leaves turn an attractive bronze colour over the winter months. For growing indoors, or taking undercover in winter, there are also related Trachelospermum asiaticum – varieties of less hardy star jasmines. The cultivar ‘Ogon Nishiki’ has variegated leaves with gold, yellow and white contrast that also have lovely autumn colouration. Why Grow Star Jasmine? Star Jasmine is predominantly grown as an ornamental plant. It can be beneficial as an evergreen climber in milder climes to cover an unattractive south or west-facing wall or fence throughout the year. This is also a good plant for attracting bees, butterflies and moths when grown outdoors. As slow-growing plants, they can be useful for small gardens in areas where they can be grown outdoors – and can also work well as houseplants where space is at a premium. But perhaps the biggest selling point for star jasmine is the delightful fragrance of the blooms. The lovely smell makes this an excellent choice for indoors areas, or for placing close to seating areas in a garden. Where To Grow Temperature & Exposure Star Jasmine can be grown outdoors where temperatures will not drop below around -5°C – and where conditions are warm in summer and relatively sheltered throughout the year. In milder southern reaches of the UK, star jasmine can be grown outdoors, though it is still best to position it with the protection of a wall – a sunny location against a south or west-facing wall will be ideal. Though a full-sun location is usually best, Star Jasmine can also cope with partial shade. Of course, in less mild and more northerly gardens, it is best to grow star jasmine indoors, or to take it inside for protection over the winter months. Star Jasmine is particularly intolerant of cold, drying winds and it can be a little fussy about temperatures and climatic conditions. Soil Requirements Fortunately, Star Jasmine does not need deep soil to grow well, so it can be grown successfully in containers – but the soil or growing medium in which it is planted must be free-draining, as this is a plant that does not like to have wet feet. Ideally, the soil or growing medium should be moderate to high in fertility, and have a neutral to alkaline pH, but Star Jasmine will also grow in slightly acidic soils. Support Star Jasmine is self-clinging, but one thing to bear in mind when choosing a position for your plant, is that it may need to be tied into some form of support until it is properly established. This is true whether you are growing it in the ground or in a container. How To Grow Star Jasmine Next, let’s take a look at how to grow Star Jasmine. Propagating Most gardeners will simply choose to purchase a plant from a garden centre or plant nursery – but to keep costs down and be more environmentally friendly, it is always a good idea to consider first whether you can propagate an existing plant (perhaps one belonging to a friend or neighbour). Star Jasmine is usually propagated by layering in spring, or from semi-ripe cuttings taken between June-October. The cuttings of Star Jasmine will tend to root better if they are placed in a propagator providing bottom heat of 15-20°C. Star Jasmine rarely produces seeds in the UK, since our summers are cooler and shorter than those in the plant’s native range, so it is not usually possible to propagate this plant from seed. Planting If you are planting Star Jasmine in the ground, dig a generous hole and fork in plenty of grit and homemade compost in the base. “For container growing, mixing in some John Innes or loam-based compost, plus some grit, can add the stability that this otherwise top-heavy plant requires,” shares Peter Lickorish, a Master Horticulturist. Worm castings from a vermicomposting system can be particularly beneficial as a soil amendment. As a woody plant, Star Jasmine may also benefit from the addition of some mycorrhizal fungi (or forest leaf litter or leaf mould) into the planting hole. This can aid in the establishment of a healthy root and fungal network below the soil. Push back the soil and firm it down. Then water well. If you are growing your plant in a container, it is best to choose one which is at least 45cm deep and 45cm wide. Make sure there is adequate drainage in the base, and that this does not become blocked by the growing medium. Ongoing Plant Care Watering Star Jasmine should always be kept well-watered, especially during the summer months. During the winter, far less watering will be required. Remember, watering needs will always be somewhat higher for container-grown plants. So if you are growing your plant in a container, it is especially important to remain vigilant and make sure that it does not dry out. Mulching & Feeding Whether you are growing in the ground or in a container, it is a good idea to top-dress the area around your plant with good-quality compost, leaf mould, or well-rotted manure in the spring. The mulch will add slow-release fertility and will also help reduce moisture loss from the soil or growing medium. Especially if you are growing in a container, it is also a good idea to apply an organic liquid plant feed every month or so through the growing season. A balanced liquid feed such as a compost tea could be ideal. A seaweed liquid feed could help in making sure that your Star jasmine has all the micro-nutrients it needs for optimum health. To train your plant to grow upwards, provide canes, or stakes set at an angle towards the trellis structure, fence or wall that you wish it to climb. Tie in young plants as required, until it self-clings, then simply tie in any stray or wandering shoots to send them in the right direction as required. Pruning Guidelines Not much pruning will be required but remember ‘the three D’s’ and prune out dead, damaged or diseased shoots on established climbers as required. Maintenance pruning is best done in the spring. If necessary, you can also do a radical renovation of a mature plant and cut back all shoots by two-thirds. This is best done immediately after flowering, in August. New shoots should then break forth from the base of the plant and remaining branches. Some thinning of these new shoots may then be required. You can also prune to shape if a mature plant is getting out of control, but with this relatively slow-growing plant, this is not usually a concern. “I find the elegant twisting of the foliage and the red hue in winter especially endearing,” Peter adds. “This can be accentuated by training stems in a less dense way, such as an espalier shape on a wall. “Equally, I have seen them clipped to form a dense mass of foliage to fill a small, square wall complete with a crisp edge.” Consider growing some star jasmine where you live and enjoy its beautiful appearance and attractive blooms. Care for it well and it should be a plant that rewards you well in the years to come. References 1. Star Jasmine (Trachelospermum jasminoides). (n.d.). iNaturalist. Retrieved March 24, 2023, from https://www.inaturalist.org/taxa/169856-Trachelospermum-jasminoides 2. Rojas-Sandoval, J. (2022b). Trachelospermum jasminoides (star-jasmine). CABI Compendium. https://doi.org/10.1079/cabicompendium.52837
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How To Grow Wisteria - Choose These Types For Cascading, Beautifully Fragrant Flowers
IN THIS GUIDE Overview Wisteria Varieties How To Grow Wisteria Wisteria Care References Effortlessly beautiful and timelessly charming, Wisteria is famously known for the pendulous clusters of lilac, white or bluish flowers it produces in late spring and early summer. Often seen draping itself over arches and pergolas or climbing its way up the walls of a country cottage, wisteria is a serious showstopper. Across our wisteria guides, we’ve partnered with Chris O’Keefe, Owner of The London Wisteria Company and O’Keefe Gardens Limited. “There is nothing like the scent and feeling wisteria gives you whilst in bloom,” Chris says. “I’m lucky to live and work in central London where, in spring, places such as Chelsea and Kensington are in full bloom with wisteria showcasing the frontage of many homes.” Overview Botanical Name Wisteria Plant Type Climber Native Area East Asia, Eastern United States Hardiness Rating H6 Foliage Pinnate leaves Flowers Racemes of purple, pea-like flowers When To Sow January, February, March, April, October, November, December Flowering Months May, June Wisteria is a vigorous climbing shrub, and is actually a legume, making it part of the pea family (Fabaceae).1 As previously mentioned, wisteria adorns itself with cascading, beautifully fragrant lilac, blue or white flowers. The stems are stiff and woody, and the trunks can become as thick as a small tree. There are ten species of wisteria, with the most popular and widespread being native to China, Japan and North America.2 Wisteria Varieties With ten species to choose from, it could be hard to know where to start. We’ve chosen a few of the most popular to grow: Chinese Wisteria Botanical Name: W. sinensis This wisteria twines itself anti-clockwise and can grow from about ten to twenty-five feet, sometimes even higher. It can also be trained horizontally over the same distance making it a popular choice for a wall or side of a house. The chains of fragrant flowers, which are violet in colour, grow to about a foot in length and bloom in late spring or early summer gradually over a few weeks. This species has small oval-shaped leaves that usually will be bronze in colour when they are young. Japanese Wisteria Botanical Name: W. floribunda The Japanese wisteria can grow up to 30 feet or higher and will also grow the same amount horizontally. This species twines clockwise and has oval leaves that turn a beautiful yellow colour in autumn. The flowers are usually violet and heavily scented, and their blooms last much longer than their Chinese counterpart. This is a reliable choice and is wonderfully decorative and perfect for arches. Silky Wisteria Botanical Name: W. brachybotrys This Chinese wisteria variety twines anticlockwise, with fine, silky-soft leaves. Hence its name. The lilac or white flowers bloom from late spring to early summer, and the bloom will improve with age. The clusters of flowers grow to about six inches in length and are strongly scented. The silky wisteria grows to twenty-five feet and often higher and is perfect for walls. Kentucky Wisteria Botanical Name: W. frutescens var. macrostachya This American species is native to the midwest, Louisiana and Texas. It twines anticlockwise, and its pale violet flowers bloom in late spring or early summer. The clusters grow to the length of up to one foot. This wisteria can grow from fifteen to twenty-five feet and will often bloom again during the growing season. American Wisteria Botanical Name: W. frutescens A native to the eastern parts of the United States, this wisteria twines anticlockwise and grows from ten to thirty feet. It has lilac-blue flowers, blooming in clusters of four to six inches and are not generally heavily scented. This species will bloom primarily in late spring and then sporadically throughout summer. How To Grow Wisteria While it is possible to plant and grow wisteria from seeds, you should expect to wait up to twenty years for its famous flowers to bloom (typical estimates range from 10-20 years).3 For this reason, we recommend that you buy a plant raised by grafting. However, be aware that even with a grafted plant, you may have to wait up to five years for it to bloom. “Wisterias must surely have a little ticking clock inside them,” says Peter Lickorish, a Horticultural Consultant. “My Wisteria flowered for the first time exactly five years after planting it, to almost within a month, and has flowered abundantly since. It really is like the flick of a switch.” The best time to plant wisteria is between October and April, although if you opt to grow it in a container, you can do this at any time of year. Garden Planting You will want to plant your wisteria in fertile, well-drained soil and preferably in a south or west-facing direction. Being the vigorous climber that it is you will need to support them against a wall, or another garden structure, wires or even a tree. Full sunshine is preferable, but they will tolerate a little shade. Although this may reduce their flowering. Container Growing As mentioned, if you are planting in a container, this can be done any time of year. That said, wisterias are easier to care for in the autumn and winter months. The container should be at least eighteen inches in depth and should be filled with a loam-based potting compost. Do be aware that a container-grown wisteria will not be as successful as those planted in a garden. Wisteria Care Now you’ve planted your gorgeous wisteria, the next step is learning how to care for it. Watering Wisterias can dry out quickly, especially in sandy or light soil. Make sure you water them frequently, especially during dry spells. Feeding In springtime, we recommend a high potash feed to encourage those gorgeous flowers. Rose or flowering shrub fertiliser will also work. If you are growing your wisteria in a container, then liquid tomato fertiliser is ideal. You could also use slow-release fertiliser in compost. Propagating As previously mentioned, wisteria grown from seed is said to take up to twenty years to flower, so if you want to share the wealth with friends and family or just stock up for yourself, then we recommend taking softwood or hardwood cuttings. Take softwood cuttings in spring to mid-summer, and hardwood cuttings in winter. If you’d like to try growing from seed, collect the bean-like seed pods from an established plant, then place in a tray to allow them to ripen. Next, gently open the pod and place in compost at a depth of about two centimetres. If you find, upon opening the pod, that the seed is dry, then place in water and soak it for 24 hours before planting. References 1. Harris, S. (n.d.-f). Wisteria sinensis. Oxford University Plants. Retrieved March 27, 2023, from https://herbaria.plants.ox.ac.uk/bol/plants400/Profiles/WX/Wisteria 2. Utah State University. (2022, August 3). Wisteria in the Garden. Retrieved March 27, 2023, from https://extension.usu.edu/yardandgarden/research/wisteria-in-the-garden 3. How to grow wisteria. (n.d.). Royal Horticultural Society. Retrieved March 27, 2023, from https://www.rhs.org.uk/plants/wisteria/growing-guide
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Chris Lee On His 10 Favourite Climber Plants For Shaded Garden Areas
IN THIS GUIDE 1) Climbing Hydrangea 2) Climbing Roses 3) Honeysuckle 4) Star Jasmine 5) Clematis 6) Ivy 7) Virginia Creeper 8) Passion Flower 9) Chilean Bellflower 10) Mitre Flower All plants need light to grow, but that doesn’t mean the shady parts of your garden are doomed to be barren. Some familiar and attractive flowers can thrive in the shade, and in this article, we round up a few of the best ones. If you’re looking for climbing plants that do well in the shade – look no further. While there are fewer plants that thrive in full shade than other conditions, you still have a lot to choose from. The shade-loving climbers in this list will bring life and vibrant colour to the formerly-subdued areas of your garden. If you’re looking for the best plants to grow on your north and east-facing walls or fences, let us give you a hand. 1) Climbing Hydrangea BOTANICAL NAME: Hydrangea petiolaris HARDINESS RATING: H5 SUNLIGHT TOLERANCE: Full Shade TYPICAL GROWING HEIGHT: 10M+ While some climbing plants require support, climbing hydrangea – full name Hydrangea petiolaris – clings all by itself. This self-clinging ability is a boon to gardeners with shaded walls or trellises, as it requires no manual intervention beyond watering and occasional pruning. This variety of hydrangea is a big plant, expect a height of over 12m once it’s fully grown, with a spread of up to 8m. It’s hardy, too, making a fine addition to British gardens. With climbing hydrangea, you’ll enjoy white flowers in summer, fading to yellow in autumn. 2) Climbing Roses BOTANICAL NAME: Rosa HARDINESS RATING: Typically H5-H7 SUNLIGHT TOLERANCE: Part Shade TYPICAL GROWING HEIGHT: 2-8M If you’re not so keen on the hydrangea aesthetic, why not consider roses instead? Although not all varieties are built to grow in the shade, certain types are up to the task. Here are a few to get you started: R. ‘Alberic Barbier’ Creamy yellow flowers that grow from strong stems to a height of up to 8m over 5-10 years. R. ‘New Dawn’ A smaller plant, reaching a maximum spread of about 2.5m. New Dawn has pale pink-white flowers that will burst out in early summer and stay until autumn. R. ‘Wedding Day’ Less thorny than some other varieties, with glossier leaves. White flowers with a yellow centre and a distinctive shape. Will reach a maximum of about 8m high. R. ‘Danse du Feu’ The name means ‘fire dance,’ and evokes the vibrant red of this rose variety. This really is a special plant to behold and will take well to shade. See more varieties of climbing roses for shade in this guide. You’ll need to tie the stems of climbing roses help them climb a wall or trellis. This can be done with bands of soft fabric, and they don’t need to be tied too tight. It’s not recommended to prune your climbing rose until it covers the whole trellis, doing so may stunt its growth. 3) Honeysuckle BOTANICAL NAME: Lonicera HARDINESS RATING: Typically H5-H6 SUNLIGHT TOLERANCE: Part Shade TYPICAL GROWING HEIGHT: 2-4M This plant is renowned for its inviting scent, and for its ability to flower multiple times in a growing season if deadheaded. It combines very well with other climbing plants. Take a look at the image above for an example – rose and honeysuckle provide beautiful coverage for this cottage wall. Climbing honeysuckle is prone to attract aphids and other pests, so stay vigilant if you choose this plant for your garden. Keep an eye out for small bugs, or for any visible damage to leaves. If you see either, quickly take the relevant steps to remove pest infestations and prevent damage to other plants in your garden. Like hydrangea, honeysuckle plants don’t need to be tied onto fences and trellises. Unlike hydrangea, however, they will need support when growing up a wall. 4) Star Jasmine BOTANICAL NAME: Trachelospermum jasminoides HARDINESS RATING: H4 SUNLIGHT TOLERANCE: Part Shade TYPICAL GROWING HEIGHT: 8-10M Another famously fragrant plant, star jasmine will do well in east-facing parts of your garden. Unlike some of the other plants in this list, it requires a little bit of sunlight rather than full shade. We’ve included nonetheless to give you some options. The dainty white flowers have a really interesting shape. It’s a five-pointed star (hence the name), but with a slightly different nuance to other star-shaped flowers you’ll come across. 5) Clematis BOTANICAL NAME: Clematis HARDINESS RATING: Typically H6 SUNLIGHT TOLERANCE: Part Shade TYPICAL GROWING HEIGHT: 2-4M We’ve seen clematis described as ‘born to climb’ – and with good reason. Certain varieties of this plant are known as the fastest-growing climbing plants, so if you’ve got a wall or trellis that you want to cover quickly, you may be in luck. Here are some climbing varieties that will do well in shade: C. viticella ‘Black Prince’ These striking dark-red, almost-black flowers sit especially well alongside climbing roses, and will thrive in part shade. C. alpina Bold and exciting purple flowers grace this variety of clematis. They droop pleasingly when closed, then stand proud when open. 6) Ivy BOTANICAL NAME: Hedera HARDINESS RATING: H5 SUNLIGHT TOLERANCE: Full Shade TYPICAL GROWING HEIGHT: 8-10M Ivy is probably the first plant that pops into your mind when somebody mentions climbers. “Ivy is a great choice for a shady climber and there is either the common species, Hedera helix, which will find its way to a vertical space in your garden whether you want it to or not, or many cultivars of varying hues,” says Colin Skelly, a Master Horticulturist. “It is tough and tolerant to wet or dry and different soil conditions, but I particularly like it because, when mature, its flowers in autumn are a brilliant nectar source and hum with life.” You’ll see this plant out in the wild, winding its way up buildings, fences, even trees. It’s a keen grower, even in dark shade, and brings colour and striking shapes to any outdoor space. If you’re wondering what vine grows well in the shade, you need to look no further than Parthenocissus tricuspidata, also known as Boston ivy or Japanese creeper. Its green leaves fade to red in autumn, bringing a medley of colour. This plant will cover an enormous amount of site if given time, up to 12m high by 8m wide. 7) Virginia Creeper BOTANICAL NAME: Ampelopsis quinquefolia HARDINESS RATING: H6 SUNLIGHT TOLERANCE: Full Shade TYPICAL GROWING HEIGHT: 10M+ If you want a plant that will dominate a shaded wall, you’re in luck. Virginia creeper has big leaves and can grow quickly to cover an impressive area. It’s easy to take care of, too, thanks to its suckers. No need to tie it onto a trellis, or otherwise support the growth. The Chinese Virginia creeper (Parthenocissus henryana) is another popular climbing plant for shade. This variety will show more vibrant leaves if it gets a bit of sunlight during the day, so if this is important to you, make sure to grow it somewhere east-facing. You can be creative when choosing a climbing plant for shade. Rather than choosing one plant, why not select a couple whose colours, shapes, and growing habits complement each other particularly well? Shade-loving plants will bring real vibrancy to the formerly drab parts of your garden and combining multiple will keep things vibrant for more of the year. 8) Passion Flower BOTANICAL NAME: Passiflora HARDINESS RATING: H4 SUNLIGHT TOLERANCE: Part Shade TYPICAL GROWING HEIGHT: 6-10M 9) Chilean Bellflower BOTANICAL NAME: Lapageria rosea HARDINESS RATING: H3 SUNLIGHT TOLERANCE: Full Shade TYPICAL GROWING HEIGHT: 3-4M 10) Mitre Flower BOTANICAL NAME: Mitraria coccinea HARDINESS RATING: H3 SUNLIGHT TOLERANCE: Full Shade TYPICAL GROWING HEIGHT: 1-2M Grow In Pots Or From The Ground? When choosing the best climbing plants for shade in your garden, you have the option of growing them in pots or in the ground. Sometimes, this decision will be made for you. In a paved alleyway or a patio, for example, you’ll have to rely on pots. A clematis climbing its way up a shaded trellis If you’re growing a climbing plant up a fence, wall, or trellis with soil beneath it, you can plant the climbers right into the ground. This will let them grow larger than from a pot, so make sure you take this into account. Nobody wants to be surprised by a much larger plant than they bargained for!
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Choose To Grow Climbing Hydrangea For A Sprawling Garden Favourite
IN THIS GUIDE Overview Habitat & Growing Conditions Planting Plant Care & Growing Tips Preferred Sunlight Soil Requirements Pruning Propagation Where To Grow More Climbing Varieties Common Problems References Visualise a lush vertical sheet of dark green foliage up to 15m high, sprawling and spreading across the side of your summer house or up a wooden trellis, and bearing delightful, wavy clusters of white or creamy little flowers throughout summer. Like that vision? Be introduced to the Climbing Hydrangea. That near-ubiquitous garden favourite, the little Hydrangea plant, has a few less well-known relatives. These are the less-ubiquitous, not-so-little, Climbing Hydrangeas. Of the few thousand Hydrangea varieties, a mere handful are climbers. Overview Botanical Name Hydrangea petiolaris Common Name(s) Climbing Hydrangea Plant Type Climber Native Area Japan and South Korea Hardiness Rating H5 Foliage Deciduous, broadly oval leaves Flowers Showy white flower heads When To Sow April, May Flowering Months May, June, July When To Prune March, July, August For the most part, they are deciduous woody vines that climb using adventitious aerial roots that are not damaging to bricks or to other trees. A supplementary means of climbing is that the vines and branches themselves entwine around support structures, also holding fast using suckers. Although most Climbing Hydrangeas are deciduous, a couple are evergreen. However, whether a particular vine is deciduous or evergreen also depends on the climate: if the winters are mild, Climbing Hydrangeas may not shed their leaves. Hydrangea petiolaris Most species are native to a geographical area stretching from Siberia and Sakhalin through Southern China, Taiwan, Korea and Japan, stretching down to the Himalayas, India, and Myanmar in the South.1 Only two species make their home in Mexico, Central America, and the Southern United States.2 Different varieties attain different heights, but the tallest ones can grow up to 30m. If a Climbing Hydrangea has nothing to climb up on, it will creep along the ground, over time covering up to 60m². It forms pretty mounds about 1m tall, providing an attractive ground cover of lush undulating foliage richly dappled with white in the summer. Habitat & Growing Conditions Constant sun or bright sunlight can singe this plant. A band of temperature between 15-20°C is just perfect for this vine. In contrast, Hydrangea barbara can tolerate bright sun and semi-tropical conditions much better than H. anomala, the reason being that Climbing Hydrangea species exhibit diversity in more than just ‘looks’. Hardiness also varies between the different species, subspecies and cultivars. Planting The best time to plant Climbing Hydrangea is mid-Spring after there is no danger of frost. It can be planted in summer too provided it is kept properly watered. If the plant doesn’t seem to grow, do not worry – it grows rather slowly during its first 2 or 3 years as most of its energies are spent on developing and spreading its root system. Thereafter, upon becoming established it will grow much more rapidly, even as much as 1m per year. However, it will take about 5 years for it to start developing flowers. It takes 10-20 years for Climbing Hydrangeas to reach their full height. Plant Care & Growing Tips Preferred Sunlight Climbing Hydrangeas grow well in part shade to even full shade. Ideally, these plants should get some sunlight in the morning or evening, with shade or only dappled sunlight during the peak hours of the day. That said, in cold or temperate climates they can tolerate near-full sun. Soil Requirements What they cannot tolerate, however, is dry soil. In dry soil, the vine will wither and it may even die. This climber must be watered regularly and the soil should be kept consistently moist. The soil itself should be rich and fertile; best results are obtained in soil with humus or compost. It is not picky about pH, growing in soil ranging from moderately acidic to slightly alkaline. Feed Climbing Hydrangea with a slow-release fertiliser in early spring so that it will last through mid-summer. Pruning If you want to prune this climber, cut back vines as soon as flowering has finished, doing so before the appearance of fresh buds. If you delay this pruning and cut off vines with buds, it will result in a sizeable reduction in blooming the following year. In early spring, prune the dead flowers and other growth killed during winter. You may be lucky enough to inherit a Climbing Hydrangea or get it as a bonus on some property. If such a plant is unkempt and overgrown and you want to bring it to manageable proportions, do not prune it suddenly; prune it gradually over 3 years. You can shape or trim this plant by cutting off unwanted vines at the point they join the stem. Cut off dead, damaged, or unwanted stems at the plant’s base to kick-off fresh growth just before the growing season commences. One practical reason to prune this vine would be when it is climbing up a wall rather than a trellis, tree, or anything else that it can entwine itself around. When Climbing Hydrangea scales walls, it can rely only on its aerial roots and suckers which are not as strong as they are in other climbers. If the plant gets too bushy and heavy away from the wall, it may topple or slip. To avoid such a possibility, prune the climber so that it is flatter against the wall. Propagation Schizophragma hydrangeoides Climbing Hydrangea is best and most easily propagated by cuttings although horticulturalists also propagate it from seeds. Take cuttings between April and June before the advent of flowering season but after the start of fresh growth: Sterilise a pair of secateurs with diluted rubbing alcohol. Choose a shoot that has leaf nodes and emergent aerial roots and cut it at a point below the roots so that the length of the cutting is about 25cm. Press the cutting into rich and fertile soil that is loamy or peaty. The emergent roots and at least some of the leaf nodes should be underneath the soil’s surface. Water the cutting and ensure that the soil stays moist but not waterlogged. The cutting and the young plant may get partial sun but it should be protected from the afternoon sun or harsh sunlight. New growth should be observable in two to three weeks. Where To Grow Climbing Hydrangea plants can be put in many places for a variety of purposes. Here are some ideas:– Grow it up and over a boundary wall or fence to create a ‘foliage fence’, pruning the vine to control its growth. Let it gradually cover a house’s wall like a vertical sheet, or use it as a substitute for ivy. Plant it by a pergola and as the vine grows, entwine it around the structure for ornamental value. Simply grow this plant for the sake of itself, as outdoor decoration, over a trellis. Use it, managing the growth, to cover up unsightly patches or damaged spots on any wall or structure. Grow it on an open part of your acreage or beside a walkway as an unusual and eye-catching ground cover. As this plant attains its maximum height and spread in about 20 years, you can plant a vine as a bequest for future generations. A Note On Support Structures Climbing Hydrangea does not ’need’ any support structure at all. Sans trellis, pergola, and such, this vine will spread in undulating mounds along the ground, sending shoots and branches horizontally in all directions. For vertical growth, Climbing Hydrangea can make use of any type of support such as trees and walls to aid it in its upward trek. However, whichever structure that this vine makes its ascent on had better be strong because over several years the plant, growing and spreading as it does, becomes quite heavy. “Climbing hydrangeas will be equally comfortable growing down a slope as up one,” shares Master Horticulturist Colin Skelly. “Planted at the top of a slope it will slowly spread downwards and across the slope. “It will also form a natural vegetation barrier at the top of the slope, which can be handy if it is steep.” More Climbing Varieties When one talks of Climbing Hydrangea, it is usually about Hydrangea anomala. This species is native to Sakhalin Island, Japan, and the Koreas.3 The genus name is a composite of ýdor (ύδωρ) and aggeion meaning, respectively, water and vessel, describing the appearance of the plant’s seed capsules.4 A mere handful of other species exist. H. anomala This species can grow up to 12m. From late May to July it bears corymbs that can be 15cm across. These are composed of a ring of sterile showy flowers that are white enclosing a clutch of small fertile flowers ranging in colour from creamy white to greenish-yellow. This formation is called ‘lacecap’. It bears fruit from September to October. This is an unusual plant whose bark exfoliates, that is it peels off. It prefers part shade to full shade. H. petiolaris A subspecies of H. anomala, this hydrangea is so named because of its long and distinct petioles. It can grow considerably taller than the species, up to 20m, and its floral corymbs are also bigger with a diameter of 25cm. It has better winter hardiness than the base species. H. petiolaris ‘Miranda’ (or ‘Firefly’) More bushy and lush than its subspecies, the cultivar ‘Miranda’ (or ‘Firefly’) spreads more as well because it puts out lateral branches that grow away from the vine’s structural support, to a length of 2m. H. hydrangeoides (Japanese Hydrangea Vine) This variant from Japan is known for its leaves which are about 10cm long and are toothed and heart-shaped. It bears large lacecaps about 23cm wide. These comprise of cream-coloured small flowers ringed by showy white sterile flowers. H. barbara The only Climbing Hydrangea that is native to the United States, growing in the South-East, this climber has glossy leaves of a deep shade of green.5 Its white-to-cream floral clusters have a distinctly fluffy appearance. Pileostegia viburnoides An Indo-Chinese species, this vine’s narrow, elliptic leaves have a leathery appearance. It bears attractively thick panicles of cream-coloured flowers. H. seemannii This Climbing Hydrangea is an evergreen. It grows in Mexico and Central America and has large and rounded leaves and dense sprays of cream-white flowers. Common Problems Climbing Hydrangeas are one of those uncommon plants that are pest-resistant and disease-free. Any problems it may meet would have their provenance in human error or neglect. For the most part, just make sure that the soil does not dry out and that it drains well. Why Won’t My Climbing Hydrangea Bloom? First, if your plant is young then you cannot expect it to bloom. Remember that a new Climbing Hydrangea may take up to 5 years before it produces flowers. Another cause could be dry soil in warm climates – keep your Hydrangea vine watered and ensure that the soil stays moist. Yet another reason could be an excess of warm sun. Climbing Hydrangeas bloom profusely when shade predominates. Finally, a fertiliser that is high in nitrogen content or nitrogen-rich soil can adversely affect Climbing Hydrangeas’ blooming. For established vines that are not blooming, either cut out fertiliser or use 0-5-5 fertiliser to kill two birds with one stone: 0-5-5 fertiliser has no nitrogen to retard blooming and contains phosphorous (besides potassium) which stimulates blooming. References 1. Hydrangea anomala. (n.d.). Missouri Botanical Garden. Retrieved March 20, 2023, from https://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?taxonid=286935 2. Hydrangea barbara (Climbing Hydrangea, Woodvamp). (n.d.). North Carolina Extension Gardener Plant Toolbox. Retrieved March 20, 2023, from https://plants.ces.ncsu.edu/plants/hydrangea-barbara/ 3. Climbing Hydrangea (Hydrangea petiolaris). (n.d.). iNaturalist NZ. Retrieved March 20, 2023, from https://inaturalist.nz/taxa/410578-Hydrangea-petiolaris 4. ὕδωρ (Ancient Greek). (n.d.). Word Sense Dictionary. Retrieved March 20, 2023, from https://www.wordsense.eu/%E1%BD%95%CE%B4%CF%89%CF%81/ 5. Lady Bird Johnson Wildflower Center. (n.d.). The University of Texas at Austin. Retrieved March 20, 2023, from https://www.wildflower.org/plants/result.php?id_plant=deba4
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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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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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