Clematis at the cutting edge

They could be lying through their stamens, but, hopefully, July and August are set to be a couple of scorchers.

But those self-same flowers also provide a major headache for many a gardener – do you prune to keep a montana within bounds; and how do you prune any clematis?

So, it’s time to sharpen the secateurs and get to grips with the clematis pruning régime.

C montana is a bit of an exception – it is so rampant that it’s often more a case of hacking it into shape rather than carefully trimming it to meet its needs.

But with the late summer bloomers, like ‘Ville de Lyon’ and that gloriously seductive ‘Comtesse de Bouchard’, things are very different.

Pruning clematis is a task steeped in myth and mystery; despite the British gardener’s penchant for growing vast numbers of this most beautiful of flowering shrubs, when it comes to keeping them in shape and encouraging them to bloom again, when to cut, where to cut and how to cut are three questions which crop up annually. It’s simple when you know to which group your clematis belongs. Then, pruning becomes just another annual chore.

Basically, clematis fall into three groups – those which have small flowers in spring and summer; those which have large flowers in mid-summer; and those which bloom in late summer, like the aforementioned ‘Ville de Lyon’ and ‘Comtesse de Bouchard’.

All you need to remember is that the first two groups need pruning immediately after they have finished flowering, while the late bloomers need cutting back hard early in the year to encourage fresh growth. It’s on those new shoots that this year’s flowers will appear. So, just cut all the stems right down to the bottom pair of buds; in fact, almost to the ground.

The only time you serve up the same sort of treatment to the spring and early summer bloomers is when they are newly-planted; by pruning them to shape then, you encourage stronger growth and a sturdier framework for future years.

But if in doubt, leave well alone.