Q. I need to know when to trim clematis. I have tried for 10 years to grow them. I now have three growing. One is so tall, and I want to know how to keep it full and blooming. &emdash; Veneda Hoesel, Winamac, Ind. A. If you categorize clematis by their pruning needs, there are three different groups. Group one blooms in the spring on last year’s new wood. Little pruning is needed except for […]