Seed to Harvest Growing Guide

How to grow cauliflower

A practical guide to starting unstressed transplants, timing a cool-season crop, protecting and blanching the curd, and cutting compact heads before heat loosens them.

Grow without stress to prevent buttonsSpace 12–18 inches for full leavesBlanch white curds from sunlight
Botanical illustration showing cauliflower seed, seedlings, transplants, a forming white curd, and mature white, purple, and orange headsCrop family: Brassicaceae
Start6–7 weeks earlyBefore transplanting outdoors
Depth1/4–1/2 inchKeep the mix evenly moist
LightFull sunAt least 6 hours
Spacing12–18 inchesRows 24–36 inches apart
HarvestAbout 50–90 daysUsually counted from transplant

Before you begin

Give cauliflower a long stretch of steady cool growth.

Cauliflower is less forgiving of stress than most brassicas. Compact transplants must establish without cold shock, drought, low fertility, or root restriction, then form curds in cool weather before heat makes them loose, leafy, or discolored.

Best first decisionChoose the harvest window first. Fall crops are often easiest where summers are hot, while self-blanching types simplify keeping white curds shaded.

Build your cauliflower-growing plan

Plan the cool window, transplant count, blanching method, and harvest target.

Reserve a sunny, well-drained bed and time the crop so compact curds form in mild weather rather than summer heat.

Cauliflower at a glance

The path from seed to harvest

Select any milestone to jump directly to its full instructions.

Stage 1–3

Start compact seedlings and prevent every transplant shock

Cauliflower must build enough healthy leaves before curd initiation; overmature, chilled, dry, or root-bound transplants often button.

01

Prepare a fertile bed

Choose full sun and well-drained soil rich in organic matter.

  • Use a soil test to guide lime and fertilizer.
  • Rotate away from brassicas for disease control.
  • Plan for row cover before planting if caterpillars are common.
02

Start seed indoors

Sow 1/4–1/2 inch deep about 6–7 weeks before transplanting. Keep the mix moist and give seedlings strong light.

Transplant targetMove plants outdoors with 4–6 mature leaves and a well-developed root system. Do not over-harden or hold them until oversized.
03

Harden and transplant

Gradually acclimate seedlings, then set them out about 2–3 weeks before the last spring frost.

  • Space plants 12–18 inches apart.
  • Leave 24–36 inches between rows.
  • Plant at the same depth or slightly deeper than the cell.
  • Water immediately and protect from wind.

Stage 4

Keep growth uninterrupted from transplant to curd

Cauliflower needs even moisture, steady nutrition, cool roots, and timely shading for clean compact curds.

W

Water evenly

Supply about 1–2 inches of water per week, including rain. Keep the root zone consistently moist as the head develops.

F

Feed by test

Cauliflower is a moderately heavy feeder. Follow a soil test and side-dress nitrogen when plants are established if needed.

C

Keep roots cool

Mulch after the soil warms to conserve moisture, suppress weeds, and moderate temperature swings.

B

Blanch white curds

When the white curd is 2–3 inches wide, fold or tie outer leaves over it for the final 7–14 days unless the variety self-blanches.

Growth checkpoints

Know what to watch for.

Use leaf count, curd size, color, and texture—not only the calendar—to time transplanting, blanching, and harvest.

About 5–10 days

Emergence

Seedlings appear with round cotyledons; move them into strong light so stems stay short and sturdy.

4–6 mature leaves

Transplant ready

Harden compact plants gradually and transplant before they become root-bound, overmature, or stressed.

Curd 2–3 inches

Blanching time

Cover a white curd with outer leaves unless the variety naturally shields it; mark tied heads for later checking.

6–12 inches

Harvest window

Cut when the curd is full, white or true to variety color, smooth, and compact before sections separate.

Stage 5

Diagnose cauliflower problems early

Open a symptom to compare what you see, likely causes, and the next practical check.

Green cabbageworm on a cauliflower leaf with irregular chewing holes and frassPestCabbage worms and loopersRagged holes, green caterpillars, or frass around leaves and heads

Inspect leaf undersides and the crown, handpick caterpillars, and use insect netting before moths arrive. If needed, use a labeled Bacillus thuringiensis product on small larvae and follow the label.

Cauliflower leaf with yellow V-shaped lesions and darkened veins from black rotDiseaseBlack rotYellow V-shaped lesions advancing inward from leaf margins

Remove infected plants and residue, avoid overhead irrigation and working among wet plants, rotate away from brassicas, control crucifer weeds, and begin with clean seed and transplants.

Small premature cauliflower button head on a stressed young plantGrowth disorderButtoningA small premature head forms before the plant has enough leaves

Buttoning often follows overmature transplants, cold injury, nutrient stress, or interrupted growth. The head will not enlarge normally; correct timing and grow compact, unstressed transplants for the next planting.

Loose ricey cauliflower curd with green bracts and slight yellowing after heat stressHeat stressLoose or ricey curdCurd separates, turns coarse, yellows, or grows small leaves through it

Heat, drought, delayed harvest, and direct sunlight reduce curd quality. Maintain even moisture, schedule curd formation for cool weather, blanch white heads, and harvest promptly once compact.

Stage 6

Cut curds while they are smooth and compact

Harvest when the curd reaches the expected size and remains dense, clean, and true to variety color. Heat can change perfect heads quickly, so inspect daily near maturity.

  1. Check: Open blanching leaves and look for a full 6–12 inch curd with tightly packed sections.
  2. Cut: Use a clean knife below the head and leave several inner wrapper leaves attached for protection.
  3. Cool: Remove field heat promptly and refrigerate unwashed at high humidity.

Choose with purpose

Find the right cauliflower for your season and table

Compare maturity, self-blanching habit, curd color, heat tolerance, head size, and organic seed options.

Questions gardeners ask

Cauliflower growing FAQ

Quick answers for timing, seed starting, spacing, transplant stress, blanching, compact curds, harvest, and storage.

When should cauliflower be planted?

For spring, transplant compact plants about 1–2 weeks before the average last frost. For fall, count backward from cool harvest weather using variety maturity plus the time needed to raise transplants.

Is cauliflower better direct sown or transplanted?

Both work, but transplants give more timing control. Start seed indoors about 6–7 weeks before planting out and avoid overmature, root-bound, or over-hardened plants.

How deep should cauliflower seed be planted?

Sow 1/4–1/2 inch deep in seed-starting mix or finely prepared soil. Keep evenly moist and give emerged seedlings strong light.

How far apart should cauliflower plants be spaced?

Space plants 12–18 inches apart with rows 24–36 inches apart. Ample space supports the large leaves needed to feed and shade a quality curd.

Does cauliflower need full sun?

Yes. Give plants at least six hours of direct sun, but schedule curd formation for cool weather. Hot conditions reduce curd quality even when plants receive enough light.

Should cauliflower be grown under row cover?

Insect netting or lightweight row cover can exclude cabbage moths and flea beetles if installed immediately and sealed at the edges. Vent or remove covers before excess heat builds.

Why are worms eating my cauliflower?

Imported cabbageworms and cabbage loopers commonly feed on brassicas. Check leaf undersides and the crown, handpick larvae, and use netting or a labeled biological control while larvae are small.

Why did my cauliflower make a tiny head?

Buttoning follows stress before the plant has enough leaves—often overmature transplants, cold exposure, drought, low nitrogen, root restriction, pests, or disease. The tiny curd will not enlarge normally.

Why is my cauliflower curd loose or ricey?

Heat, drought, rapid growth, and delayed harvest cause curd sections to separate, become coarse, or grow green bracts. Time crops for cool weather and harvest compact curds promptly.

How much water does cauliflower need?

Provide about 1–2 inches per week, including rain, and keep moisture uniform from transplanting through curd development.

How do I keep white cauliflower from turning yellow?

When the curd reaches 2–3 inches wide, fold or tie outer leaves over it for 7–14 days. Self-blanching varieties naturally shield the curd and may not need tying.

How should harvested cauliflower be stored?

Cool heads promptly and refrigerate them unwashed in a perforated bag or loosely wrapped container. Use within about a week for best home-garden quality and wash just before preparation.

Ready to plant?

Choose cauliflower for your garden.

Compare days to maturity, white or specialty color, self-blanching habit, heat tolerance, organic options, and packet size.

Shop all cauliflower seed →