"Rupert (W.Yorkshire)" writes

"K" wrote in message
...

It depends on the species and on how dry the soil in their pots is. It is
possible to keep eg Opuntias outside all winter in S England if bone dry.

If the freezing itself has done damage, I'd expect that to show up quite
quickly, but if they're damp as well it may well be not till spring that
you find out they've rotted off.

I don't think it'll be 'lasting damage' as such - they'll either survive
unscathed or die completely.

I try to keep my greenhouse above 40 deg F but still have a few nights
where it's dropped to 32 deg. The cacti survive, mostly.


TRICHOCEREUS PASACANA and TRICHOCEREUS TERSCHECKII are being offered for
availability next year as 0.6-1m plants and are being promoted as hardy?
What do you reckon ?.

Dunno! I don't like Trichocereus ;-)

"In winter they should be kept cool and dry, in which conditions many
species will tolerate night frosts" Cullman, Gotz and Groner "The
Encyclopaedia of Cacti"
- doesn't sound very hopeful - we can't guarantee the frost doesn't
continue for several days on end. But I'm not up to date with cactus
knowledge.

I suppose big volume things might survive even a
cold Yorkshire winter assuming they have very good drainage.

You need more than good drainage - you need a rain shelter, and not let
the soil get wet at all through the winter.

Are there any genuine hardy cacti in the UK (excluding deep south) ;-)

Not AFAIK

Not cacti, but I have some ?Aloe (spotted leaves and spires of bright
orange flowers) and Echeveria in a window box - been there years, but
then they're getting the benefit of heat loss through our toilet window.



--
Kay