Clematis are climbing plants that provide height and colour to a garden throughout the summer. There are a huge variety of plants to choose from, in many colours and with flowers ranging in size from small bell size to large dinner plate size. Covering walls, fences and trellis with leaves and flowers, they are also good for wildlife, providing shelter for insects and sometimes birds.
All photos by Toni and Diane Abram.
Most clematis require moisture retentive soil and full sun (think roots in the shade, top growth in the sun), so need watering regularly, particularly in dry weather. They’re hungry feeders, so need a high potash fertiliser such as tomato feed in the summer. This is particularly important when growing clematis in pots – clematis are suited to a range of planting locations, however as a general rule, do better in garden soil than in containers. Feeding your clematis should encourage a healthy crop of flowers.
How to plant clematis
Clematis should be planted in spring or autumn. Dig a hole twice the width and depth of the root ball and part fill it with well rotted organic matter and some bone meal or other fertiliser. A clematis will benefit from being planted around 5 cm deeper than it was in the original pot, as this can prevent the fungal infection known as clematis wilt.
Remove the plant from its pot, place the root ball in the hole and back fill with soil, firming in well and watering thoroughly. Continue to water the clematis every week or so until it starts to show healthy signs of growth.
How to prune clematis
While all clematis have roughly the same planting needs, they need pruning according to their pruning group.
- Group one
Flowers on wood created the previous year, so doesn’t require any pruning at all.
- Group two
Also flowers on the previous year’s growth and should be lightly pruned in February, removing damaged or weak stems to make way for fresh growth, then trimming other stems to just above the strongest and highest pair of buds.
- Note: If cut back too hard, you’ll lose a year of flowers
- Group three
Flowers 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.
Note: If you don’t prune group three clematis, you’ll end up with a tangled mass of stems with flower growing only at the very top of the plant
How to take clematis cuttings
The best way to take clematis cuttings is to take softwood cuttings in April or May. The short film below shows how to do this.
- Wilted shoots
Clematis wilt is a fungal disease which can cause clematis to die suddenly without apparent reason. Larger flowered types are the most likely to be affected. If affected, all stems should be pruned and burned.
Clematis are also prone to attacks from earwigs. The damage is only cosmetic and doesn’t harm the plant but you can create earwig traps by pushing a 1m long cane into the ground next to the clematis, stuffing a plastic plant pot with straw and placing this upturned on the top of the cane. Earwigs will use this as shelter during the day, giving you the opportunity to catch and re-home them.
- Rabbits, mice, slugs and snails
Rabbits, mice, slugs and snails like to eat clematis, so protect young plants to give them a good start.
For further information about growing clematis, visit the websites below.