In my effort to get courgettes started early to beat the squash vine borers, I'm wondering how cold is too cold?
Near-term, moving them indoors at night as needed should be no problem. Mid March though, we may have nights that dip to 5 C for an hour or two in the early morning, warming later to 15 C. Can seedlings cope with that, or is it too cold?
Put another way, how cold can seedlings tolerate?
Thank you