March to me is pruning month, the time to get out those secateurs and into the garden for a good old sort and tidy. Time spent now in the garden always pays off and prevents more work later on when things have grown and gone a bit wild.
So to clematis. Now don’t panic and please keep reading. It’s not as hard as some make out and the worst you can do is cut off potential flower buds for this year and, if that is the worst thing you do this year, it’s not that bad is it?
If you are planting new clematis, or did so last autumn, plant deep, give a good mulch and prune to a decent bud about 30cm (1 foot) from the ground. That way you will set it up to grow good, strong roots and many flowering stems. Keep it well watered and tie it in regularly.
Clematis fall into 3 groups:
Group 1: Those that flower in Spring such as C. montana, C alpina and C. armandii. You don’t need to prune these at all (hooray!) but C. Montana especially can get huge and threaten the integrity of your gutters. So if you need to tidy it, do so in early summer after flowering. Then new shoots will grow and ripen and be ready to flower next year.
Group 2: these flower on shorter stems coming out of the previous seasons old wood. These tend to be larger flowering hybrids such as Nelly Moser and Vyvyan Pennell. They are less vigorous and need a gentler prune to a nice fat bud. I usually take them down to about three feet, but it will depend what your plant is growing up or through and what effect you want.
Group 3: These flower later on, some into the autumn, and the flowers come on the new wood produced this year. These should be cut down to about 30cm again to prevent all the flowers coming at the top of the plant. Don’t be tempted to prune too lightly or you will end up with loads of nasty brown tangly stems with flowers way above your head! C. Jackmanii and the lovely Viticellas fall into this group. The Viticellas are some of my favourite, such beautiful, elegant and dainty flowers, they are brilliant scramblers. Knocks the spots of the ubiquitous Nelly Moser any day in my book, but each to their own!
Then give them all a feed, water and mulch. Clematis love potash so you can buy sulphate of potash and sprinkle that around before you water, or if you are burning some wood they love fresh (but not too hot!) wood ash.
We have loads of clematis at Charnwood. Some growing up through climbing roses, other scrambling up trees and a gorgeous larger flowered white one (sorry, name long forgotten) brightening up a Pyracantha in the summer. You always have space for a clematis! I have just bought a new one called Ernest Markham from Moores for a meagre £4.99. Lovely plant. He’s small so will take a couple of years to get going properly but patience is part of being a good gardener I’m afraid!