By Carmich
United Kingdom 
My Wisteria has progress quite well over a 4/5 year period and is producing a number of flowers in late April early May. Unfortunately as the flowers start to bloom the green leaves overwhelm the flowers and spoil the display, there are also long off-shoots that require control well before the recommended summer pruning time of July / August. Can I prune in May and how can I reduce the amount of leaves – Any advise please.
Car mich
29 Apr, 2011
Yes you can prune out any excessive leaf while its in flower - but the proper way to prune wisteria is, as you already do, in August, and then again late winter, by mid February - when you reduce shoots again, avoiding cutting off any 'fat' buds which may be flowers.
30 Apr, 2011