When to plant cauliflower 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). Cauliflower needs 60–90 days to mature, which fits comfortably within Missouri's growing season.
When to plant cauliflower 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 cauliflower 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 7.5. 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. It needs plenty of water; keep the soil evenly moist and never let it dry out.
- Watch for pests and problems. Pests: cabbage worm, cabbage looper, aphids, cabbage root maggot. Diseases and disorders: clubroot, black rot, downy mildew.
- Harvest (from about May 31 – Jun 30). Cauliflower takes 60-90 days to reach harvest. The fussiest brassica - any check from cold, heat, or drought ruins the head. Fall crops are far more reliable than spring. Blanch white types by tying leaves over the curd.
Figures come from our crop data; dates use Missouri’s average frost dates. More in the full cauliflower growing guide.
Cauliflower 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 cauliflower dates shift with them.
When to plant cauliflower in nearby states
Questions gardeners in Missouri ask
When is the best time to plant cauliflower in Missouri?
Plant cauliflower 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 cauliflower 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 cauliflower 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 cauliflower planted in Missouri be ready to harvest?
Planted on time, cauliflower is usually ready from about May 31 to June 30, 60-90 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.