When to plant broccoli in Missouri
Missouri’s average last spring frost is April 15, and the first fall frost typically arrives around October 18 — about 186 frost-free days (USDA zones 5b, 6a, 6b, 7a). Broccoli needs 60–85 days to mature, which fits comfortably within Missouri's growing season.
When to plant broccoli in Missouri: the short answer
For a spring planting, plant out Mar 25 – Apr 11, with seeds started indoors Feb 25 – Mar 11. Seeds germinate in soil from 45 to 85°F.
Windows are ~1–2 week bands around each date. Frost dates are a statewide average from NOAA/NCEI normals; your town may differ by two weeks or more. Calendar year 2026.
How to grow broccoli in Missouri, step by step
- Start seeds indoors (Feb 25 – Mar 11). Sow seeds ½ inch deep in seed-starting mix under bright light. They take 5-10 days to sprout, fastest in soil around 75°F. Harden seedlings off for a week before they go outside.
- Prepare the bed. It needs at least six to eight hours of direct sun a day and loose soil at least 18 inches deep, with a pH between 6.0 and 7.0. Dig in compost before planting.
- Plant out (Mar 25 – Apr 11). Space plants about 18 inches apart in rows 30 inches apart. It tolerates a light frost but not a hard freeze. As a cool-season crop it does best before summer heat arrives in Missouri.
- Water and feed. Give it steady, even moisture, about an inch of water a week from rain or the hose.
- Watch for pests and problems. Pests: cabbage worm, cabbage looper, aphids, flea beetle, cabbage root maggot. Diseases and disorders: clubroot, black rot, downy mildew.
- Harvest (from about May 31 – Jun 25). Broccoli takes 60-85 days to reach harvest. Days to maturity counted from transplant. Keep cutting side shoots after the main head for weeks. Spring crop must size up before heat or it buttons.
Figures come from our crop data; dates use Missouri’s average frost dates. More in the full broccoli growing guide.
Broccoli planting dates by USDA zone in Missouri
Missouri spans USDA zones 5b, 6a, 6b, 7a. Colder zones, usually higher or further inland, have a later last spring frost and an earlier first fall frost than the state average, so the broccoli dates shift with them.
When to plant broccoli in nearby states
Questions gardeners in Missouri ask
When is the best time to plant broccoli in Missouri?
Plant broccoli transplants outdoors in Missouri between March 25 and April 11. That timing is set by Missouri's average last spring frost of April 15.
When should I start broccoli seeds indoors in Missouri?
Start seeds indoors between February 25 and March 11, about 6 weeks before the last frost, so the seedlings are ready to plant out from March 25.
Can I plant broccoli in the fall in Missouri?
Yes. For a fall crop, start transplants between July 9 and July 26, so the crop matures in cool weather before Missouri's first frost around October 18.
When will broccoli planted in Missouri be ready to harvest?
Planted on time, broccoli is usually ready from about May 31 to June 25, 60-85 days after transplanting.
When is the last frost in Missouri?
On average around April 15, with the first fall frost around October 18 - about 186 frost-free days. Your town may differ by two weeks or more.