Quick! Before the frost hits, harvest all of the green tomatoes left on your plants. Make sure the tomatoes aren’t touching (to prevent rot) and keep them in a dark warm spot. I stowed mine in a clementine orange box. I shoved half an egg carton inside to keep the small rolly cherry tomatoes apart. I stuck the clementine box on top of the fridge (a warm spot) and put a cardboard box over top to keep the light out. Approximately three weeks later I have ripe tomatoes.