You should be fine. It grows like a weed and will emerge when its ready.

around here it overwinters and sets seeds in April/May, which then sprout whenever conditions are right, often in late summer/fall (yes, it has naturalized). Not sure how to advise you, tho, as I never saw sprouting seeds getting frozen.

I have tried to grow this for two years now and it fails for me. Will only germinate using the paper-towel method and then the sprouts never emerge from the soil after the seeds are planted. I grew 5 plants in the greenhouse, but can't seem to get it to grow in the garden. Everyone says "it almost grows itself!" well, I must not have the knack for it.

Once you get it going, definitely learn what it looks like when going to seed and leave it alone -- last winter I had it in half my beds, this winter I ended up with one whole 4foot by 25 foot bed of it (all self planted) and we've been eating salads every day the snow is off.

However, I don't see much reason to plant it now, as it's no good in warm weather. Maybe plant now so that it goes to seed and gives you a bed of it for next winter?

runswithscissors -- keep trying. Maybe buy some different seed (there are two kinds -- get the most cold hardy kind for your area). It'll be worth it. Maybe try planting in the fall -- I normally plant it in September or October.

I think it grows much like lettuce, bok choy.
I have sown some in my cold frame but they have not yet emerged. Now that it is getting milder, they should germinate any day now.

I always knew it as a winter vegetable.

While it is more of a winter vegetable, seeing as you are in zone 2, I would go ahead and try it. Seed is relatively cheap and if it does not work for you, you could probably try again.

Runswithscissors, I have had problems with it too. I am still trying to get the right conditions for it and have not found them yet but I want to keep trying. I really enjoy it but suspect my timing may have been off in the past.