We have an old (40-50 years, I think) and extremely vigorous wisteria on
the south wall of the house - its trunk is probably some 10 cm in
diameter. Unfortunately, it is bent, and very close to where we are
going to have to have replacement windows installed sometime very soon
(and we may have to sell the house soon after that).

There are lots of shoots coming out of the roots, and I have tied some 8
of the best-placed ones to a cane with the idea that these can take over
when the main trunk has to be cut.

My hope is to have as mature a replacement wisteria as possible, as soon
as possible, in case we do have to sell. With this in mind, should this
be treated like a new young wisteria, or is there a way of taking
advantage of the huge old roots to make the whole mature more quickly?

My question is: is it better to have more stems, in order to have a
thick, twisted trunk - or would just a few grow better than 8?

Also, the shoots are very long already. Should they be cut at the
highest point, with the aim of getting side-shoots eventually, or should
they simply be given a 90-degree angle and be tied in horizontally from
that point on?


Thanks in advance for any advice!
--
Klara, Gatwick basin