Clematis are popular perennial climbers, providing height and colour throughout the season. They look particularly good with roses. There’s a huge variety of clematis to grow, with flowers ranging in size from small bells to large dinner plates.
Clematis can be good for wildlife, clothing walls, fences and trellis with leaves and flowers, which provide shelter for insects and sometimes birds. Some clematis flowers are visited by pollinators, while the fluffy seedheads of Clematis tangutica cultivars may be used as a nesting material by house sparrows.
How to grow clematis
Most clematis require a fertile, moisture-retentive soil and full sun, but there are some that tolerate shade. They’re hungry feeders, so add plenty of organic material when planting and feed weekly with a high potash fertiliser in summer. All clematis have roughly the same planting needs, but need pruning according to their pruning group (see below).
More on growing clematis:
Clematis: jump links
- Choosing clematis
- Planting clematis
- Caring for clematis
- Pruning clematis
- Taking clematis cuttings
- Pruning clematis
- Clematis problem-solving
- Best clematis to grow
Find detailed planting and growing advice for clematis, below.
Choosing the right clematis
There’s such a wide variety of clematis available, that it’s important you choose the right clematis for the spot you want to grow it in. Some clematis, such as Clematis montana, are extremely fast-growing and vigorous, and are suitable for covering an unsightly wall or shed in a short space of time. Other clematis have a much less vigorous growth habit, and are therefore suitable for growing in pots – look for growth habit on the label or varieties such as Clematis ‘Blue Dwarf’, which indicates a less vigorous habit.
Ther are plenty of clematis varieties suitable for sun and shade, so again check the label to see how well suited your clematis is to the spot you have in mind.
Lastly, consider how much care you want to give your clematis. If you’re happy pruning your clematis annually, then Group 3 clematis are perfect for you. However, if you’d like to keep pruning to a minimum then opt for a Group 1 or Group 2 clematis.
Where and when to plant clematis
All clematis do best when their roots are in shade and top growth in the sun. As a rule, most clematis do best in garden soil rather than in containers. If growing clematis in a pot, plant in John Innes no.3 with added grit.
The best time to plant clematis is in late spring or early autumn, when the soil is moist and warm, but not too hot. You can plant clematis in summer, but you’ll need to water it more frequently to help it establish well. Avoid planting clematis in winter.
Clematis are suited to a range of planting locations. Less vigorous types are suitable for growing up a trellis, while rampant climbers such as Clematis montana and Clematis jackmanii can be planted at the base of a large wall or shed, and trained to cover it. Other types are perfect for scrambling through trees, and you can even grow clematis as ground cover.
How to plant clematis
Prepare the soil
Plant clematis in spring or autumn. All clematis varieties do well in moisture-retentive soil, so prepare a deep planting hole and add a bucket of garden compost or well-rotted manure. Mix this thoroughly into the soil.
Position the rootball
Position your clematis in the hole so that the top of the rootball is level with the soil surface, or 6cm below for large-flowered types (pruning group three). Remove lower leaves, fill around the roots with soil and firm down.
Water your clematis thoroughly after planting and then every two weeks in the first three months. Cover the soil surface around the plant base with tiles or stones to keep the roots cool and moist, which can prevent the fungal disease clematis wilt.
Tie in stems
Tie in the new clematis stems regularly using soft twine or foam-covered twist ties. Take care not to break the stems and space them evenly to maximise coverage over their supports.
How to care for clematis
Clematis are hungry, thirsty plants. Water regularly in dry weather and feed with a high potash fertiliser, such as a tomato feed, just before they start to bloom. This is particularly important when growing clematis in pots. The feed should encourage a healthy crop of flowers.
In our Golden Rules video, Marcel Floyd of Floyds Climbers and Clematis gives his top tips on caring for clematis, including why it’s important to prune them right after buying. He also reveals when to water and how best to feed them:
How to prune clematis
Clematis are divided into three pruning groups, as follows:
Group 1 clematis flower on wood created the previous year. They therefore don’t require any pruning at all.
Group 2 clematis also flower on the previous year’s growth and should be lightly pruned in February. Simply remove damaged or weak stems to make way for fresh growth. Then trim other stems to just above the strongest and highest pair of buds. If cut back too hard, you’ll lose a year of flowers.
Group 3 clematis flower on the current season’s growth. Prune plants hard in early spring, before growth begins. Cut back plants to just above a healthy bud about 30cm from the soil. If you don’t prune Group 3 clematis, you’ll end up with a tangled mass of stems with flower growing only at the very top of the plant.
In this video clip from Gardeners’ World, Monty Don explains how to prune a summer-flowering (Group 3) clematis:
How to propagate clematis
The best way to propagate clematis is by taking softwood cuttings in April or May. Remove a section of stem from the current season’s growth, which is ripe but not too woody or too soft. Fill a garden pot with cutting compost and water. Add a fine layer of grit to the top of the compost.
Cut a section of the stem above a leaf joint. Your cuttings should be about 7cm long. Remove some of the leaves so each cutting is left with just one. Push the end of the cutting into the pot so it supports itself.
Cover the pot with a clear plastic bag or place in a propagator and leave in a warm place but out of direct sunlight. Cuttings can take up to five weeks to root.
In this video, Monty Don guides you through the process of taking clematis cuttings. Using the variety ‘William Kennet’, he shows you which stems to select, how to trim them ready for planting, how deep to insert them, and how to provide the conditions they need to root successfully:
Clematis can also be propagated by layering, simply take a low-growing stem and peg it to the ground with a tent peg or similar. You can propagate clematis from seed but the offspring of the large-flowered hybrids will vary from the parent plant.
Growing clematis: problem solving
Clematis wilt can cause huge problems for clematis, growers, causing clematis to die suddenly without apparent reason. Larger flowered types are the most likely to be affected. It’s easy to spot as plants quickly wilt. Clematis wilt is a fungal disease. Prune out all affected stems and burn them.
Clematis are also prone to an attack from earwigs, which chew holes in the flower petals. This damage is only cosmetic and doesn’t harm the plant. If you’re really concerned you can create earwig traps by pushing a 1m long cane into the ground next to the clematis. Stuff a plastic plant pot with straw and place it upturned on the top of the cane. Earwigs will use this as shelter during the day, giving you the opportunity to catch and rehome them.
Advice for buying clematis
- Make sure you choose the right clematis for the right spot – choose shade-tolerant clematis if you don’t have much sun, and compact clematis if you have a small garden or are growing clematis in pots
- Bear in mind that specialist clematis growers will have more choice, but you may find a bargain at some of the larger garden centres or online retailers
- Check your clematis thoroughly for signs of damage before planting
Where to buy clematis
Best clematis to grow
Clematis ‘Vyvyan Pennell’
Impressive giant, double, pale purple blooms in May, June and September. Height 3m.
Buy Clematis ‘Vyvyan Pennell’ from Thompson & Morgan
Clematis ‘Nelly Moser’
‘Pyjama-striped’, pink and pale-lavender flowers from May-June. One of the best clematis for shade. Height 3m.
Buy Clematis ‘Nelly Moser’ from Van Meuwen
Clematis montana ‘Freda’
Single flowers of four petals, white and pale pink in May and June. Height 6m.
Buy Clematis ‘Freda’ from Primrose
Clematis viticella ‘Confetti’
Delicate pink flowers in July and September. Height 2m.
Buy Clematis ‘Confetti’ from You Garden
Clematis ‘Perle d’Azur’
A popular old clematis with sky blue flowers in July to September. Height 3m.
Buy Clematis ‘Perle d’ Azur’ from Thompson & Morgan
Clematis tangutica ‘My Angel’
Small, bell-shaped pink-yellow flowers in late summer followed by stunning fluffy seedheads. Height 2.5m.
Buy Clematis ‘My Angel’ from Thompson & Morgan