Wisteria Death ?

[megfitz]

One of my Wisterias, About 15 years old, grown on a Pergola (North facing but protected by next-doors Leylandii hedge) leafed as usual, the flowers weren't as plentiful as last year but healthy looking, looked at it on Wednesday to find the flowers and leaves brown, shrivelled and dead looking, no whippy bits for pruning back. the odd thing is another Wisteria two supports away and opposite side looks fine so far.
What has caused this? is it fatal? can I do anything to protect the other one? Is it caused by this heatwave? Any advice please. Thanks for help.

[Chipchopper]

I think what you suspect may true, the intense heat has had a drastic reaction in my garden.
My Saskatoon, (Amalanchier) which had some good berries developing, suddenly, yesterday shriveled on the bush, even though it was in part shade and kept watered!
The best advice, I think is to keep well watered and put a good depth of mulch around the roots.