I have a beautiful clematis 'crystal fountain' in my garden, which is growing really rapidly. I have been training up my trellis as it grows, but quite a lot of the stems are tangling around each other. Should I try to prevent this, or is this all part of the course. Also, when do I prune them? They are deciduous,. so do I just trim throughout the summer when they start to go over the boundary, or do I wait until next year and then chop back completely?
Any advice welcomed!