Cutting back a clematis

Asked May 2, 2015, 7:30 PM EDT

We have a beautiful clematis plant, very mature. About three to four feet of it from the bottom up is nothing but vines. From that point upward it has beautiful, deep purple flowers. The plant is about 10 feet tall. We were thinking about trimming it back or cutting it off so that we can get it to fill in at the that wise? Could it damage the plant to do that? Is there a way where we cut back 30% or something and slowly try to get it to fill in at the bottom? Or should be just count our blessings and leave it alone even though it's pretty bare for the first 4 feet up the plant? Thank you in advance for your recommendation.

Clackamas County Oregon pruning clematis horticulture

1 Response

There is very little you can do that will harm your clematis once established. It's not clear from your message that it is a spring blooming type (blooms are formed on growth from the previous year) or if it's a summer blooming type (blooms form on the current years growth.) for the former, I think cutting ~1/3 of the main vines to about 6 inches will promote the lower growth. It may take two years to see blooms. If it's the latter type, I would recommend cutting a third back this fall (to the same 6") after it's done blooming. I suspect next spring you will be rewarded with a flush of new growth at the bottom. I have both types in my yard. the spring blooming is clematis montana which covers a cyclone fence. I do trim it after blooming but it covers at least 20 feet of fence. the summer blooming is on my front porch and I cut the whole thing to the ground each winter and it grows to about eight feet on the railing.