I’m in USDA Hardiness Zone 4b-5a, meaning I have a short growing season with late frosts in spring and early frosts in fall. However, many cold-hardy crops can be planted right now (March 21), especially if you use row covers, cold frames, or raised beds to extend the season.
Cold-Weather Crops to Plant in March (Direct Sowing or Transplants)
These crops can withstand light frost (28-32°F) and even some hard freezes (below 28°F).
Leafy Greens & Brassicas (Cold-Hardy, Tolerates Frost)
✅ Spinach – Grows best in cool weather, direct seed now.
✅ Lettuce (Romaine, Butterhead, Leaf) – Hardy and can be planted now under protection.
✅ Kale – Very cold-hardy, plant seeds or transplants now.
✅ Swiss Chard – More heat-tolerant but can handle cold weather.
✅ Mustard Greens – Grows quickly in cold weather.
✅ Arugula – Cold-tolerant and fast-growing.
✅ Cabbage – Start transplants outdoors with row covers.
✅ Broccoli – Start transplants outdoors.
✅ Brussels Sprouts – Best started early as they take a long time to mature.
✅ Cauliflower – Needs protection but can be planted early.
Root Vegetables (Cold-Hardy, Best for Direct Sowing)
✅ Carrots – Takes longer to germinate in cold soil but does well once sprouted.
✅ Beets – Can handle frost and cold soil.
✅ Radishes – One of the fastest-growing cold crops (ready in 30 days!).
✅ Turnips – Tolerates cold and frost well.
✅ Parsnips – Takes longer to germinate but loves cold weather.
Alliums (Onion Family)
✅ Onions (Sets or Transplants) – Plant now for summer harvest.
✅ Garlic (If not planted in fall, can be planted now for smaller bulbs).
✅ Leeks – Cold-hardy and great for early spring planting.
Peas (Very Cold-Hardy)
✅ Sugar Snap Peas
✅ Snow Peas
✅ Shelling Peas
Tips for Success
✅ Use row covers or cold frames – Protects from frost and extends the season.
✅ Plant in raised beds – Soil warms faster in spring.
✅ Water deeply before frost – Moist soil retains heat better than dry soil.
✅ Watch nighttime temps – Cover crops if temps drop below 25°F.
Would you like a customized planting calendar for your area? 🌱