"judith" wrote
Growing for the first time in the garden. All sprouted OK but they
are now looking a bit sorry for themselves: leaves about 5 or 6 inches
long - but slightly brown/yellow. It has of course been quite cold
over the last two weeks - frosts or just above at night.

Is this their normal colour - rather than a nice green ;-)

Should I feed them?

I hate to say this but ours is about a foot high and has, as usual, come
through the winter quite untroubled. It's now growing away nicely.
Can't imagine the weather having the effect you mention, it's as tough as
old boots.
I think you might have a case of Rust, quite common on Garlic but much later
in the season usually, it also usually doesn't do much damage although in
this case it is early and I have known someone lose the crop because of it
in the past.

--
Regards
Bob Hobden