Fall frosts don’t have to end your salad season. With the right cold frame, you can extend lettuce production well into winter. Cold frames act like mini greenhouses, trapping daytime warmth and protecting tender greens from overnight freezes. Even simple designs can raise soil temperatures just enough to keep cool-weather crops thriving. Whether you’re growing on a patio or in a backyard bed, here are seven cold frame styles that keep lettuce crisp, sweet, and harvest-ready long after the first frost.
