Fall and winter crops for extended harvest

Many cold-hardy vegetables not only survive frost but actually improve in flavor after exposure to freezing temperatures. Cold triggers plants to convert starches to sugars as an antifreeze mechanism, making kale, carrots, parsnips, Brussels sprouts, and leeks sweeter after frost. Plant fall and winter crops 8-12 weeks before your first expected frost date so they reach near-maturity before short winter days slow growth. Top performers for fall/winter raised beds: kale (survives to 10 degrees F, harvest all winter in zones 6+), spinach (cold-hardy to 15 degrees F under light cover), carrots (leave in ground under heavy mulch, harvest as needed through winter), garlic (plant in October/November for summer harvest), lettuce (winter varieties like Winter Density and Arctic King under cold frame protection), mache/corn salad (extremely cold-hardy, produces through winter). In zones 5-7, most of these crops need the protection of a cold frame or hoop house to survive. In zones 8-10, they grow outdoors with minimal protection. The key insight: plants grow very slowly in winter due to short day length (under 10 hours of sunlight), so they must be nearly full-grown before the solstice. Time your planting accordingly.