January 1, 2021

By Kate and Len Lucas

Previously we have tried to avoid telling gardeners “what to do”. With Clematis, however, for the best flower display, we can’t avoid some of the “what to do”. And that’s because when to prune plays a vital role.

The temptation in the winter is to cut everything down to the ground including your Clematis. Some of them will flower and some of them will flower a lot later than they should, and some won’t flower at all.

If you never prune any Clematis it will flower, but eventually, it will be a great mass of tangled stems and shoots and more likely flower in your neighbour’s garden.

Clematis are separated into three groups depending on when they flower and when they should be pruned. In each group, we have listed some that we have grown or are growing in our own garden today.

Group 1.

These will flower on the stems that grew last year, or if you like, on stems that are one year old. So if you were to cut them down in the winter they will grow but won’t flower. Prune them immediately after flowering. Here are some of the first Clematis to flower.

Clematis cirrhosa “Freckles”
Evergreen and useful just for that. It could come into flower as early as January. This is an elegant plant once it gets going.

Clematis alpina “Constance”
The flower buds will appear early in the spring and, like all alpinas, are not difficult to prune. This is one of our favourites.

Clematis montana ”Tetrarose”

Montanas are vigorous so you can be really tough on them by cutting out all the stems that have just finished flowering. The whole plant will grow back quickly to flower next year.

All the varieties of Clematis cirrhosa, alpina and montana should be pruned the same way i.e. immediately after flowering.

Group 2.

These should be pruned in the spring before growth starts and needs patience, time and care. All you have to do is start from the top of each stem and work down until you come to a strong bud. Then cut just above it to take out all the old dead growth. Do that on each stem and you can’t go far wrong.

Clematis “Miss Bateman”
A very old variety and will grow to about 6 to 8 feet with large white flowers that have a very red centre. A real gem.

Clematis “The President”
Another old variety. Very large purple-blue flowers and could get up to 10 feet. We have several.

Group 3.

This last group is the easiest to deal with because you can cut these down very nearly to the ground. TV Gardener, Monty Don’s advice here is to cut them down on Valentine’s Day to within a couple of buds above ground level. They grow very quickly and will flower on these new stems later in the year.

So they are flowering on what is called “first-year wood”.

Clematis viticella “Etoile Violette”
We have several of these all growing together over an arch and they will produce hundreds of blue-purple flowers in early summer.

Clematis “Golden Tiara”
We chose this because it flowers in late summer with small yellow flowers.

Clematis x triternata “Rubromarginata”
Produces long sprays of small vanilla-scented flowers in the summer. Even though it doesn’t look like a Clematis we wouldn’t be without it.

You can of course plant several Clematis together, and if you do, be careful to make sure that they are all in the same pruning group.

When you buy any Clematis from a garden centre the label will have the correct pruning group on it. If it doesn’t then just ask one of the staff to check it for you.