North Dakota · zones 4a–4a
When to plant broccoli in North Dakota.
Sow or transplant between Mar 24 to Apr 21 in a typical year, keyed to North Dakota's median last frost around May 15. A second, fall sowing fits Jun 8 to Jul 18. Dates below are state medians; your ZIP code shifts them by days to weeks.
The 2026 windows
Broccoli dates for a typical North Dakota season.
1 · Start indoors
Feb 10 to Mar 10
About 6 weeks before set-out. Warm spot, real light.
2 · Set out
Mar 24 to Apr 21
Keyed to the ~May 15 last frost. Sow 0.5" deep, 18" apart.
Fall round
Jun 8 to Jul 18
Counted back from the ~Sep 22 first frost.
Harvest
~60 days later
~1.2 lb per plant over ~3 weeks.
North Dakota spans more than one climate: Zone 4 is the most common zone, but the state runs 4a to 4a. That's why the planner works from your ZIP code's frost dates, not your zone: mountain and coastal gardens in the same state can be three weeks apart.
In North Dakota: watch for
The pests that find broccoli here.
The short season here, about 130 frost-free days, keeps broccoli in front of cabbage worms & loopers only briefly. One early row cover usually carries a planting through the worst of it.
Green caterpillars chewing ragged holes; green droppings.
Organic fix: Handpick, cover with netting, spray Bt.
Gray-green clusters tucked into the leaf folds.
Organic fix: Blast with water, then insecticidal soap.
Tiny holes peppering the young leaves.
Organic fix: Row cover from day one; diatomaceous earth.
Black rot
Yellow V-shaped wedges cutting in from the leaf edge, veins blackening inside.
Organic fix: Pull infected plants, water at the base, keep brassicas out of that bed 3 years.
Seedlings wilt, yellow and stall for no reason; white maggots tunnel the roots.
Organic fix: Row cover before the flies are up, when yellow rocket blooms; rotate the bed.
Your season math: North Dakota gives broccoli about 130 frost-free days, and it needs roughly 60 days to a first harvest. It's a one-planting crop, so time that single sowing well.
Planting broccoli in North Dakota: questions
When should I plant broccoli in North Dakota?+
In a typical North Dakota year, sow broccoli or set out transplants between Mar 24 to Apr 21, keyed to the state's median last frost around May 15. There's also a fall window: Jun 8 to Jul 18. Your exact dates shift with your ZIP code and microclimate.
When do I start broccoli seeds indoors in North Dakota?+
Start seeds inside about 6 weeks before set-out: roughly Feb 10 to Mar 10 for a typical North Dakota season.
What USDA zone is North Dakota?+
North Dakota spans zones 4a–4a, mostly zone 4. But frost dates, not zones, set planting time. The free planner uses your ZIP code's actual frost dates.
How many broccoli plants do I need?+
Depends who you're feeding. The crop page has exact counts per household size, or the free planner does the math for your family in about 60 seconds.