"Judith in England" wrote ...

I always pull up the old roots and start again from seed in the next year.

I have been reading that you can actually leave the roots to over-winter.

Any experiences? Worth while?

Yes, we tried it one year. Lots and lots of sprouts but they didn't seem to
crop as well as fresh planted ones, seemed to lack vigour. We never repeated
the experiment.
In a very mild area it would be possible to leave them in the ground and let
them grow every year, say, up a fence, where they make a nice backdrop to a
flower border.
--
Regards. Bob Hobden.
Posted to this Newsgroup from the W of London, UK