Pruning Clematis

Clematis can be a challenging group of plants to prune because there's several different varieties that are all pruned at different times of the year. And the pruning is based on when the plants flower. So we typically can break up clematis into three groups. The first are those that bloom in the springtime, typically April or May in Oklahoma. And they're pruned immediately after bloom, but no later than July because we want to give the plant plenty of time for that new growth to harden off. Now we don't have any spring bloomers here in the gardens, but we do have a number of summer blooming. The summer blooming group includes most of our common hybrids with the really large colorful flowers. And these also bloom on old wood and they also bloom on new wood. But our biggest burst of flowers, the ones that come in around June, are on the old wood. So in the wintertime, we don't want to come in and cut this plant back because we'll lose all of our blossoms. But if you do look at the plant in the winter when you come out and do your pruning, you'll see plenty of dead material. The vines are red, they're brittle, they sometimes get cold damage, and these can be cut back. And when you cut back your dead material, you want to keep cutting until you find some new live growth. And this one is going to keep going back pretty far. It could be that the entire shoot is dead, but as you go you'll see if it's still brown and flaky, we don't have living material. Now as you cut back into your fresh growth, just keep an eye on how the plant's growing. You don't want to cut into the main trunk. The other thing, when it's done flowering, we can come back and give this a heavy pruning. In fact, we can remove up to one-third, two-thirds of the plant material, tame in the size. That's a great time to rein in your clematis. But it'll also promote new flush of growth, which will bring a new set of flowers. And that's always welcomed in the garden. Now one thing that we want to look at is pruning newly planted clematis. A common problem is planting a new clematis and then just leaving it. And what happens is you end up with one or two really long shoots that just grow and grow and we don't get a nice full plant. So in the first and second year after planting a clematis, what we really want to do is cut the shoots back to about 12 to 18 inches and do this again in the first year and then in the second year. And I'm going to go ahead and just cut off all this material while I'm at it. And while it feels like we're taking away all that plant, what we're going to be doing is encouraging new shoot production to come out from the base down here and we'll end up with a bushier vine that will have many shoots and much more beauty and flowers. Now our last group of clematis is the fall blooming variety and we'll look at our sweet autumn clematis. Fall blooming clematis bloom on new growth so that means we can come in in the winter time to prune the plant for managing the size or shape. And the way we prune these is by cutting the stems back to a height of about 18 inches to 2 feet above ground level. But when we do this we want to ensure that we have at least two sets of good buds on each stem. So here's a stem coming up from the base and as we look down we can see that there's one set of buds there. They're actually starting to open with this nice weather we've had. Here's another set and another set. So I would want to cut and leave at a minimum two of these but since I want to cut it to about two feet I'm actually going to leave about three sets. And so we'll do this for all the shoots. It's a little bit of slow work but if you imagine all the new flowers that we're going to get as the plant opens up it's certainly worth a little bit of investment. Now if you want the plant to grow higher to climb a large trellis you can bring your pruning back at different heights to accommodate the structure that you're growing on.