By Jenlewis
Shropshire,
United Kingdom 
Pruning, cutting back Wisteria. I know it is not the right time yet but I am trying to plan in my head the jobs I have got to do then plan to do a gardening diary for myself so I am grateful for any help. In my front garden I have 2 wisterias growing at either end of my wall. The one by the gate is fine, I pruned it last year in February and it flowered twice this summer. The other one is in my problem corner.We never even knew it was there. It has grown up all through the trees and bushes and been so neglected that the main stem is growing away from the wall. Over the summer I have cleared out quite a bit from this corner so now can get to the wisteria. I would like to cut it back hard to about 5ft, get it back on the wall and then train it over the wall putting in wires for it to grow along. How hard can I cut it back and is February the right time to do this? Hubby worried I'm either going to kill it or stop it flowering for years but my reasoning is didn't see it flower as it is now so what have I got to lose but did promise him I would ask all your advise 1st. Have tried to include photos but that don't really show how far out it is, sorry. Thank you for any help and advice you all can give me. Jen
1 Nov, 2016
Answers
Thank you Bamboo, it is in a very shady area now but hubby thinking about getting it growing other side of wall and along the top where it will get light and I can then get to it to prune. I'm going to cut it right back.
1 Nov, 2016
I attended a talk earlier this year where the speaker said any month beginning with 'J' was the right time for pruning wisterias, i.e. June or July for summer pruning, and January for winter pruning and any cutting back (while it is dormant)
1 Nov, 2016
Not sure I entirely agree - I usually prune Wisteria in August rather than July, and then again in January or by mid February, but according to the RHS, can be done July/August and Jan/Feb. Still, that advice is a way of remembering when to do it I suppose. But for a radical cut back, not so important, its not gonna flower next year anyway...
2 Nov, 2016
Bamboo - is the principle to do major cutting while the plant is dormant? I remember my father hacking one back in April and killing it.
3 Nov, 2016
Yes, Andrewr - I thought our gardeners here were taking a big risk when they did it in September, because it still had leaves, but it grew again. on the other hand, we didn't have a cold winter that year...
Link below to RHS, which covers renovation and hard pruning lower down the page - any time between leaf fall and February, basically.
https://www.rhs.org.uk/advice/profile?pid=242
3 Nov, 2016
You can certainly do that in February - you could do it in November or December or January too - there's one on the property where I live that has a trunk nearly five feet round, and which originally covered an area about 35 feet by 25 feet; the gardeners cut it right back to the trunk, taking off everything but the trunk, two years ago, in October, and its grown massively again since then - but it hasn't flowered since because they keep pruning it at the wrong times to keep it in check.
So doing it any time from now on won't kill it - the only thing that might is if there's a problem at its graft point near soil level. Its a good idea to cut it down and train in new growth - you likely won't get flowers for a year or so though,but if its not in full sun, flowering will be less anyway.
1 Nov, 2016