LATE-SUMMER flowering clematis are always a winner and, when their autumn display draws to an end, thoughts may turn to pruning. But stay the secateurs, as what you do depends on the variety and how you’re growing it.

The three groups of clematis have different pruning regimes. The first and second ones flower in spring or early summer on the previous year’s growth.

Autumn flowering types, group three, flower on the current year’s wood, so it takes longer for these stems to grow, the buds to develop and therefore for the plant to flower. To give them enough time for this they are pruned in late winter, preferably February. Inevitably there are exceptions, but I’ll come to that.

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If you have a small garden with limited space and simply want your group three clematis to be well-behaved and climb a wall or frame no higher than two to three metres, you follow the straightforward winter prune. And this is also your approach for an arch or a pergola. Cut the stems to 30-45cm above the ground, just above a pair of healthy-looking buds. Remove last year’s growth and compost or shred the old stems. If shredding, they must be allowed to dry out to prevent them clogging up your machine.

There’s a long list of medium-sized group three clematis and everyone has a favourite, so I hope you’ll indulge me if I share mine with you. I find deep purplish-crimson verging on black utterly irresistible, and this perfectly describes the sepals of Madame Julia Correvon. Their wine colour is closer to a Rhone than Black Prince’s deep Burgundy, but they compensate with larger, fuller flowers.

If you want a more spectacular show, you can let some group three cultivars grow to as much as four metres. I can thrust my prejudice on you again by mentioning Rouge Cardinal, with its suitably coloured hats and the Jackmanii group with fine velvety sepals.

Some shades of blue always catch my eye and Perle d’Azur is no exception. Its mass of clear blue sepals blend superbly with repeat-flowering golden roses. These colour combinations make subtle companions, so I’m always looking for a chance to use them.

Medium-sized clematis cope well with a February felling but, instead of cutting the lot, you could leave a basic frame and content yourself with reducing tangly or weaker stems to ground level. This should give a longer flowering period. New shoots from older wood will flower a little earlier than on the fresh growth from the base. You might find it helpful to photograph your clematis just now as this should help work out an attractive frame for next February.

You could go even further and let some potentially large clematis rip. C tangutica Bill MacKenzie can be tamed and kept fairly low-growing with an annual haircut, but it can reach five to six metres if allowed to scramble up a huge wall, or preferably a crab apple or willow. There’s nothing to beat walking under a branch swathed in nodding, golden, little cowbells.

If you do give Bill MacKenzie and other tanguticas free rein, keep pruning to a minimum and simply thin out some of the worst tangles in February. But remember, clematis all need plenty moisture, so if you’re planting close to an established tree, you’ll have to water copiously in the first couple of years to prevent the nearby resident scoffing every drop.

Herbaceous clematis tend to be less popular with gardeners, largely because they’re hard to manage well – at least that’s my experience. I found they have a tendency to rush towards an outer supporting net, producing a tangly outer mess and a bare inner. The best solution is to use a circular support for the shrub to grow through. Whatever your solution to the problem, the plant should be trimmed back to 30cm in February.