Cold Winter Areas — Zones 1–7a
April is the bridge between the indoor seed-starting season and the first real outdoor planting in cold-winter zones. As soon as soil is workable, focus on bed prep, clearing winter cover, and making space for early direct sowing of hardy spring crops — often with row cover or low tunnels to buffer cold nights. Indoors, keep starting and potting up seedlings, and begin hardening off the earliest transplants on mild days so they are ready to go out as soon as your local frost window allows.
Indoors (fresh harvests):
- Microgreens: peas, broccoli, sunflowers, arugula
- Sprouts: alfalfa, broccoli, radish, mung
- Herbs & greens under lights: chives, parsley, mint
Crops to start indoors in good light: Lettuce, cauliflower, dill, marigold, eggplant, tomato, pepper, zinnia
Transplants to move outdoors (weather permitting — harden first): Onion, parsley, broccoli, cabbage, kohlrabi, arugula, pansy, bachelor's buttons
Crops that can be directly sown outdoors in April (assume intermittent frosts; a low tunnel or row cover makes most of these reliable): pak choi, cabbage, kale, mustard, fava bean, pea, turnip, parsnip, sweet pea
Cover crops: winter rye, fava bean, hairy vetch, red or white clover, and cover crop mixes.
Tip: This zone group covers a lot of territory. Nothing replaces talking with experienced gardeners in your area and, of course, watching the weather closely.
Use your USDA zone as a guide. Microclimates matter—coastal/urban spots run warmer; high elevation runs colder.