Hiya i have a Salix caprea 'Kilmarnock' and its starting to look a bit unmanaged so i was wondering if anyone could tell me how to prune it ive been told to cut it right back but im not sure if that's the right thing to do.
give it a little cut back in the winter or early spring not too much
I'd cut some of the branches right back and leave the rest til another year.
Bit late for pruning now. You normally would do it right after the catkins on any willow have finished. It flowers on new wood so you want to encourage it to grow new branches. BUT, as Nutcutlet says, if you are not bothered about catkins then you could cut some of it back now. No more than a third though.
We cut ours right back to within 6 to 9 inches of the point of origin of branches in the middle of May.