Onions, garlic and shallots

[Greenleaves]

I hear you teakdesk, but mine always has at least 3" of green growth above the ground before Christmas and I have never had a problem. I think a lot depends on the variety and location. When we had the snows of 2011 and 2012 I had my best crops ever.

[Snadger]

I've put half of my red onion sets in and will put half my Senshyu onion sets in soon (probably tomorrow evening after work) I'll then wait a week and plant some more and another week and plant some more.

Belt and braces approach!

[Scarlet]

I hear you teakdesk, but mine always has at least 3" of green growth above the ground before Christmas and I have never had a problem. I think a lot depends on the variety and location. When we had the snows of 2011 and 2012 I had my best crops ever.

Same here! I've always sown mine early Oct and have had growth before Christmas and a fab crop. I always plant giant garlic in Sept, garlic and onions early Oct. Usually buy my sets in the Autumn Malvern show, they get planted out as soon as I get them.
I've sown early purple wight garlic this year which is for a variety for September sowing, I'm hopeful I'll get a fab crop.

[Two_Sheds]

I would not put onion sets in too early, they could produce good growth now, ...and then bolt next year ... as Sept is mild this year.

Spot on.
It's fluctuating temps that cause onions to bolt (flower too early), so ideally they need nice steady cool weather up until spring, when they really get going.

My temps are still in the high teens, so nothing's going to be planted until late Oct/Nov