One of my tasks (pleasures) this week will be to go round the garden and give all the summer and autumn flowering clematis a prune. I often think it’s all made unnecessarily complicated with talk of flowering groups etc. Basically, if its going to flower in the next few weeks leave it alone (prune after flowering if it needs restricting). For all the rest, cut back to a pair of strong buds about 20cm from the ground and mulch with well-rotted compost. It works for me……