By Mikelledr
United Kingdom 
I have allowed a clematis Montana to grow without pruning and discovered that it now only flowers at the very top of the plant. If I prune it low now will it die or will it recover to flower all over the trellis on which it grows.
2 Jun, 2013
Answers
you can hard prune at any time once flowering is over. Montana responds well to pruning, after you have done it, it will continue to grow, and flowers will appear [next year] on this years growth.So if you do it in June[as already suggested] it will have time to grow stems for flowers next Spring.You can then give it a feed after pruning.
2 Jun, 2013
Cut back a few stems moderately leaving some foliage on, and prune the rest hard back any time in June.
2 Jun, 2013