When to harvest frost hardy plants?
I'm in zone 3 and was interested in some frost hardy vegetables like turnips, cabbage and brussels sprouts. I had a good idea of when I wanted to pull my other regular crops from just walking around this fall; how much longer can frost hardy crops like the ones listed above go for? Are there guidelines for beginners and more advanced techniques like perhaps watching day to day for weather changes? Are there any frost hardy crops out there that could also withstand a few feet of snow?