Clematis are among the most popular climbing plants in UK gardens. With the right care, they produce stunning displays of flowers from spring through to autumn.
Choosing the right clematis
There are three main groups, based on when they flower and how they should be pruned:
- Group 1 (early flowering): Flower in spring on last year's growth. Examples: C. montana, C. alpina.
- Group 2 (large-flowered): Flower in early summer on old wood, often with a second flush on new growth. Examples: 'Nelly Moser', 'The President'.
- Group 3 (late flowering): Flower in late summer on the current year's growth. Examples: C. viticella, 'Jackmanii'.
Where to plant
Clematis like their heads in the sun and their roots in the shade. Plant them where the top growth will get at least 4-6 hours of sun, but shade the base with other plants, mulch, or a paving slab.
They grow well against walls, fences, pergolas, or through trees and shrubs. Make sure there is something for them to climb – they grip with twining leaf stalks.
How to plant
- Dig a hole twice the width of the pot and slightly deeper.
- Add compost or well-rotted manure to the bottom.
- Plant the clematis 5-10cm deeper than it was in the pot. This encourages shoots from below ground if the top is damaged.
- Backfill with soil mixed with compost.
- Water well and mulch around the base.
- Tie the stems to their support to get them started.
Pruning clematis
Pruning depends on which group your clematis belongs to:
- Group 1: Prune after flowering if needed. Just tidy up and remove dead or damaged growth.
- Group 2: Light prune in late winter – remove dead stems and cut back to a strong pair of buds.
- Group 3: Hard prune in late winter. Cut all stems back to about 30cm above ground level.
If you do not know which group your clematis belongs to, watch when it flowers and prune accordingly.
Watering and feeding
Clematis need regular watering, especially in the first year and during dry spells. They are hungry plants – feed with a balanced fertiliser in spring and a high-potash feed (like tomato food) in summer to encourage flowers.
Common problems
- Clematis wilt: A fungal disease that causes stems to collapse suddenly. Cut affected stems back to healthy growth. Group 3 varieties are more resistant.
- Slugs and snails: Protect young shoots in spring.
- Poor flowering: Usually caused by wrong pruning, lack of sun, or lack of feeding.
If in doubt about pruning, leave it alone for a year and watch when it flowers. Then you will know which group it belongs to.
Written by Dave Thompson
Professional Gardener & Founder
Dave has over 15 years of experience in garden maintenance across Staffordshire. He founded Hedge Cutting Staffordshire in 2009 and has helped hundreds of homeowners create and maintain beautiful gardens. When he's not out trimming hedges or advising clients, he's testing the latest garden tools and sharing practical tips on this blog.
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