I planted some in a flower bed last year. The information I found was that it was not hardy in zone 3 but it does look like it is coming back.Try it and see. If it doesn't live you can always go shopping for more.

Plant it in the ground... I had it spread all over..
Some came & some didn't..

If it's not hardy, it may just need a little protection if you want it to be a perennial. Some leaf mulch, maybe? Not one I've tried growing, but this method seems to have worked for my mint and parsley.

I don't think you can kill that stuff! I planted one little plant and we have winters of 30 to 40 below F... the stuff is coming up every where! I keep pulling it up and it just keeps spreading. I even find it in other beds. Don't know how that happens unless it makes a seed and the birds help it move around.

Anyways, my book says it is a perennial in zones 4-9 and that it spreads to about 24". But I think each little part of it spreads 24"...then the next one spreads 24"...then the next...etc etc etc. :)