How to Grow Clematis

The most colourful of all climbing plants are Clematis. They give a delightful extra dimension to the garden and with a good selection of different varieties can provide colour throughout the summer.

They are easy to grow if you have the right conditions and prepare the ground well. Clematis dislike a waterlogged soil, so make sure drainage is adequate, particularly if planting in a pot, and take care not to overwater. Remember the golden rule “Feet in the Shade, Heads in the Sun”, meaning the roots enjoy shade, and the stem and foliage need sun. Clematis require a support of some sort, and a common mistake is to plant too close to a fence, wall or tree, so be sure to leave a minimum of 12” distance. If growing up an obelisk then you can plant directly against it.

Planting Tips

When planting dig the planting hole much bigger and deeper than the size of the flower pot; 18” diameter and depth is ideal. Break up the soil in the bottom of the planting hole and add compost. The best compost for clematis is John Innes No.3. Sprinkle a good handful of Bonemeal into the hole and mix into the loosened soilAdd a scoop of Rootgrow and sprinkle at the bottom of the planting hole (don’t mix it in). Remove the pot the place the plant carefully in the hole making sure that the top of the root ball is buried about 3” (8cm) deeper than it was in its pot and re-fill the hole with a mixture of soil and compost, firming down well. Lean the cane towards the support.

You can also plant clematis in a pot, which needs to be at least 20”deep and with good drainage holes. If growing in a pot you may need to provide additional shading for the roots, and remember not to over-water, particularly in winter.

Provide Shade

Clematis planted by a wall, fence, tree or shrub, may need regular watering especially in its first year but be careful not to overdo it if planting in the autumn.

If your clematis is planted in a hot position, where the base of the plant will be baked by the sun for a large part of the day, place bark chippings or mulch around the base to provide shade for the root system.  This will help to keep the roots cool and moist, avoiding the plant drying out so quickly.

Choose your clematis with care


Choose your variety with care – montana types are early summer flowering and very vigorous. These are suitable for covering large expanses, such as house walls. The macropetala and alpine types flower in spring and are good for scrambling through summer flowering shrubs or climbing roses. The texensis and viticella varieties are later flowering and look good growing up an obelisk or trellis. My favourite of all is Clematis texensis “Princess of Wales” which has slender rich pinky-red flowers, but the popular variety “Nelly Moser” also takes some beating.

I’d strongly advise keeping the label of the clematis once it is planted, as this will remind you of it’s pruning requirements. Some need cutting down to about 18” each year, and some are best left alone, with just a bit of tidying up. The label will tell you the precise instructions for the variety you have purchased.

We currently have a good selection of clematis and other climbing plants in stock.