How to Grow Broccoli
Brassica oleracea (Italica group)
Cool-season brassica that needs steady cool weather to form tight heads.
By the Plants by Zone Editorial Team · Reviewed June 1, 2026
About broccoli
Broccoli is a rewarding cool-season crop that forms large central heads followed by smaller side shoots. Timing is everything: it must mature in cool weather, so it’s grown as a spring or, often more successfully, a fall crop. Heat causes it to bolt and form loose, bitter heads.
When to plant and harvest broccoli
Timing is relative to your frost dates. Find your USDA zone for exact dates, or browse the month-by-month calendars.
Start seeds indoors
6 weeks before last frost (spring) or midsummer (fall)
Transplant outdoors
2–3 weeks before last frost, while cool
Direct sow
Late summer for fall crops
Harvest
Late spring and fall
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How to grow broccoli step by step
- 1
Start seed indoors ¼ in deep; transplant out while weather is still cool.
- 2
Space 18 in apart in rich, firm soil and keep consistently moist.
- 3
Feed with nitrogen for strong leafy growth before heads form.
- 4
Harvest the central head while buds are tight, then let side shoots develop.
- 5
For best results in many zones, grow as a fall crop maturing in cool autumn weather.
Common problems growing broccoli
⚠ Loose, leggy heads (bolting)
Heat or late planting — grow so heads mature in cool weather.
⚠ Buttoning (tiny premature heads)
From transplant stress or cold checks — keep seedlings growing steadily.
⚠ Cabbage worms
Row cover or Bt; inspect for green caterpillars.
✗ Keep away from
🧺 Harvesting broccoli
Cut the main head while the buds are still tight and green, before any yellow flowers open. Keep the plant in place — most varieties produce smaller side shoots for weeks afterward.
Broccoli: frequently asked questions
When should you plant broccoli?＋
In most regions you start seeds indoors 6 weeks before last frost (spring) or midsummer (fall), then transplant 2–3 weeks before last frost, while cool — or direct sow late summer for fall crops. Timing is relative to your last frost, so find your USDA hardiness zone for the exact planting dates where you live.
Why did my broccoli flower before forming a head?＋
It bolted from heat or stress. Grow it so it matures in cool weather — fall crops are often the most reliable.
Does broccoli regrow after harvest?＋
Yes — after you cut the central head, most varieties produce smaller side shoots you can keep harvesting.
Sources & review
Written and maintained by the Plants by Zone Editorial Team. Planting times are based on USDA hardiness zones and NOAA frost-date normals, with care guidance drawn from Cooperative Extension sources. Last reviewed June 1, 2026.
USDA Plant Hardiness Zone MapNOAA U.S. climate normalsCooperative Extension
Grow broccoli in your zone
See exactly when to plant and what else to grow alongside broccoli, tailored to your USDA hardiness zone.
