"David wrote in message ...
".........much to my surprise the leaves aren't especially dark. Indeed no
darker than some others we have that are green leaved.
Perhaps it's because it's still in the greenhouse and it will darken when
planted outside............"

You could try giving it/them a light feed of Miracle grow, might help to
bring some depth of colour to the plant/s.
Being inside should make no difference, unless possibly you have it at a
high temp, but over the last few weeks that's not very likely, with some a
lower temp. brings out better leaf colour.

Can I ask where you got the plants/tubers from?
If Dutch tubers then there is a chance of a few wrong ones getting into
the
batch, They produce them by the 10's of thousands, and keep them trimmed
so
that they don't flower, as this would weaken the tubers. With production
on
this scale there are always some that are better than others.
When it was first bread by Tresseder in Cardiff, it was propagated only by
cuttings, so the best stock was always selected as stock, now with a lot
being produced by Tissue culture the selection isn't so critical.


Yes, I realise I should have come to you for it :-) but it was a spur of
the moment purchase as I walked through a local GC. In a plastic packet and
no doubt Dutch grown.
It has been at high temperature in the last few weeks though, germinating
lots of seeds at the moment, allotment and all that.

I'll just have to plant it out now it's hardened off and see what happens.

--
Bob

www.pooleygreengrowers.org.uk/ about an Allotment site in
Runnymede fighting for it's existence.