My 12 year old clematis is deep purple in colour and blooms in spring. It grows up the side of my house, but the bottom is a tangled mess of dead stems/bush under all the new growth. How do I clean up this old dead mess.
Managing clematis is a little confusing if you have inherited one or if (like many of us) you bought one long ago and have forgotten what type it is. That’s because clematis fall into groups, depending on their flowering time, and the groups are pruned differently. Even if you can’t identify your plant, you can rejuvenate one of any group by cutting it down to about a foot above the ground.
Depending on the type, you might have to wait a year or two for blooms, but you will achieve a healthy, tidy plant with lots of flowers. And, by noting when it blooms exactly, you will be able to determine the group to which it belongs and then follow the instructions below in future.
Your 12 year old plant blooms in spring. If it blooms in late April or in May, then it falls into the first group, 1 or A. These flower in early spring on growth produced the previous year. Every year, you can cut these vines back quite short after flowering and BEFORE the end of July. That’s to ensure the plant has enough time time to set up next year’s bloom.
If your plant blooms in late May or June, it may be a Group 2 or B. These are vines that bloom twice! The first blooms form on the previous year’s growth and the second blooms appear on the new growth. You will want to prune this type of vine in March, cutting back the healthy stems by about a foot. Cut just above a healthy looking pair of buds. You can completely cut away any weak, tangled or dead stems.
Finally, you may want to add to your plant collection a Group 3 or C clematis. Because all their blooms are formed on new growth, they don’t appear until late July and on into fall. You can cut these vines right back to the ground in early March.