how long can I leave over wintered cabbage in the ground?
I've got some Wirosa Savoy cabbages that have, miraculously, lived through many nights of sub zero (lowest was minus 31 F, not counting the wind chill). They're still in the ground, as in still planted (not just stored in the ground). They've got hay stuffed around them, and one layer of AG 19 over top of hoops. I never have any luck with storing cabbage in the root cellar or even the fridge, but these have been super crisp all winter.
My question is, is it getting too late to keep leaving them in? Do I have another month or so before I have to pull all of them? I'm assuming they've been vernalized, and will try to bolt at some point. Anyone have an idea how long I have before that happens?
I'd love to have a fresh cabbage in April if it can wait that long.(they're also huge, so we can't eat them very fast, and I just harvested one)