"Timothy Murphy" wrote

Anyone got a secret cure for non-flowering wisteria?
I've tried strict pruning for 4 years.


They like, indeed require, full sun for at least a good part of the day to
flower well. Then they do require time to get big enough to flower, I forget
how many years it took ours to flower but it took it 5 years to start to
growing well and it was some years later before it flowered. That was after
I'd pruned it so it made flowering spurs. In the wild it grows up large
trees and only starts to flower once it's reached the top and is in full
sun.

Neighbours are having a similar problem to you and from what I can see it's
down to pruning, first they didn't prune hard enough for years and then they
went over the top and cut back to old wood removing any flowering buds/spurs
that might have grown.
Once the plant has covered what you want it to and it's making side growths
then prune all this years growths back to 5 leaves during the growing
season. Then in the winter when the leaves have gone prune them further back
to two buds, I do this just before Christmas. Only cut back to old wood out
of necessity.

--
Regards. Bob Hobden.
Posted to this Newsgroup from the W of London, UK