Give your clematis a ponytail

[attach]6049[/attach]It’s hard to gauge how many of the clematis varieties we grow in our gardens are thanks to breeder extraordinaire Raymond Evison, but whatever the number, his influence is huge. If there’s a Josephine, Crystal Fountain, Arctic Queen or Rebecca twining its way up a trellis in your garden, it’s due to this delightfully charming plantsman who hails from Guernsey, that lovely little island in the English Channel off the coast of Normandy and loosely tied to Britain, that’s neither here nor there.

When Evison was in town last month, he spoke of a new technique that takes the mystery and confusion out of pruning clematis. With his newest Boulevard Collection of container clematis, he puts an end to the hemming and hawing (should I cut the vine to the ground or not?) and the frustrating quest for pruning groups (Group 3? Group A? Group “I give up!”).

He calls it the “ponytail cut” — an apt name for this simple technique. Just grab a clump of stems by the hand and with one fell swoop of the secateurs, cut them all off at about 15 centimetres above soil level. That’s all there is to it. In our climate, it’s time for a ponytail cut in late spring, just as the buds begin to swell.

There are six stunning varieties of these compact Boulevard clematis available, including the bright pink Abilene, dusky red Picardy, purple Chevalier, pale blue Diana’s Delight, deep violet Fleuri and pale blue violet Parisienne. Perfect for summer containers, they need to spend the winter in a frost-free environment, such as a cool basement or garage where temperatures don’t dip below freezing, but are cold enough to put these beauties to sleep until kissed by spring sunshine.

When potting them up, Evison also recommends giving the roots plenty of wiggle room, planting them in containers at least 45 centimetres deep. (The potting soil should have a high fibre content to help retain moisture, but not so much the roots will rot — ProMix #4 is recommended.) And be careful when choosing the pot shape, he warns, ruefully recounting how he planted some vines in containers that had elegant nipped-in necks only to realize the plants were almost impossible to remove when he wanted to transplant them.

When it comes to container materials, terra cotta is better than plastic, he advises, which heats up too much for the comfort of the roots, which appreciate a bit of shade. Combine these container clematis vines with shallow-rooted perennials such as dead nettle (Lamium) or perhaps ‘Roseanne’ geranium which will shade the roots without competing for precious container space.

There, that’s all there is to growing these new diminutive clematis vines, so get out and buy some: chop, chop.

Planting up clematis vines, Lorraine Flanigan writes from her garden in the South Eglinton neighbourhood of Toronto.