D’you think I should throw a tarp over it if the temp threatens to drop below 30?
Depends on how big it is. If it gets up a couple of inches, it should— :) — be ok. I’ve had older lettuce out in low 20’s and it was fine. Much lower than 10 degrees and I don’t think it made it. Too much cold sometimes makes it bitter, just like too much heat. Had some of the most beautiful red sails one year—the only thing it was fit for was centerpieces!