In article , JennyC
writes
I have masses of self seeded Californian poppies coming up ATM in the
gravel on my roof garden.....

Will they survive the winter ?

They may do - I have a vague memory of a few seedlings surviving the
winter here, though they were very much the exception. But unless you
have exceptionally good insulation, your roof will be warmer than my
garden.
--
Kay Easton

Edward's earthworm page:
http://www.scarboro.demon.co.uk/edward/index.htm