Questions and Answers
I have 2 clematis montana trained across the front of a bay window. They are 10 years old and glorious in the spring but they have never been pruned. When should they be pruned and cut right back to the ground? I haven't pruned them as I am frightened I will lose them.
Clematis montana falls into the group of clematis that do not require regular pruning to stimulate flowering. However, if plants have outgrown their space then pruning should be carried out after flowering in mid to late spring but only once the danger of frost has passed. General pruning can be done by simply shearing over-long branches and dead, tangled or winter-damaged shoots back to pairs of healthy buds. If you want to re-invigorate the whole plant (and after ten years you may want to do this) then cut back all stems to strong pairs of leaf buds about 12 inches (30cms) above soil level. Angle your pruning cuts so that water runs off the cut surfaces. Once pruned, apply a general fertiliser and mulch around the base. If conditions are dry, apply plenty of water during the first growing season after pruning. Plants can take more than one year to fully recover, so flowering may be reduced in the spring following pruning. If you are frightened about losing the whole plant, consider reducing down to 12 inches (30cms) over two or three springs rather than in one go. This will be less of a shock to the plant, but it will mean reduced flowering during that extended period.