How to grow cauliflower
Family Brassicaceae. Hardy to USDA hardiness zone 3a+ (U.S. Department of Agriculture). Full sun. Ready in 60-85 days.
Sun
Full sun
Spacing
18-24 in
Days to harvest
60-85 days
Hardiness
Zone 3a+
What growers actually recorded
Loading zone 7b results…
When to plant cauliflower
- Start indoors: ~6 weeks before last frost.
- Transplant out: ~-2 weeks after last frost.
Companion plants for cauliflower
Plant with: Dill, Onion, Spinach, Beet.
Avoid near: Tomato, Strawberry.
Common pests & problems
Cabbage worm, aphid, flea beetle, clubroot in acidic soil.
Feeding & fertilizer
N-P-K ratio: High N (10-5-5): heavy feeders
Organic options: Aged manure or compost worked in deep · Blood meal or feather meal side-dress at 3 wks · Fish emulsion every 2 wks
When to feed: Feed heavily every 2-3 weeks. Brassicas want steady nitrogen for tight heads.
Watch for: Pale/yellow leaves = needs N. Loose heads = feed harder next round.
N = nitrogen (leaves), P = phosphorus (roots and flowers), K = potassium (fruit and disease resistance). How to read a fertilizer label →
Grower's tip
Cauliflower is the fussiest brassica: any check in water or nitrogen makes it button into a tiny head. Blanch white types by tying outer leaves over the curd.
When to plant cauliflower in your zone
Free month-by-month sowing and transplanting lists, built from frost dates for your USDA (United States Department of Agriculture) hardiness zone.
Soil & water for cauliflower
Soil & pH
6.5-7.5: near neutral (raises club-root resistance)
Fertile loam with strong drainage. Firm soil beats fluffy for heading brassicas.
Compost 2 in + 1 cup of alfalfa or feather meal per 10 sq ft. Lime if pH is under 6.5. It also blocks club-root.
Watering
1-1.5 in / week, consistent
Ground-level drip. Uneven water during heading = split heads or bolting.
Lift an edge of the row and check soil at 3 inches. If it clings in a damp ball, hold off. If it crumbles, water until the top 6 inches are evenly moist.
Knowing when to harvest
- Curd is dense, tight, and 6-8 in across depending on variety; still fully white or its bred color.
- Cut before curds start to separate into loose, ricey segments, a sign of over-maturity or heat stress.
- Check every 2-3 days once curds appear; cauliflower moves from ready to overripe fast in warm weather.
Storing & keeping
Refrigerate unwashed in a perforated bag at 32-40°F for 1-2 weeks. Blanch 3 minutes and freeze for longer storage; does not can well due to texture loss.
What to expect
Per plant: 1 head, 1-3 lb
Per sq ft: 1 head per sq ft
Troubleshooting cauliflower
Small, premature 'button' heads
Likely cause: Transplant shock or a cold spell while seedlings are still small
What to do: Harden off transplants gently and avoid setting out before soil is reliably above 50°F.
Curd turns yellow or purple-tinged in sun
Likely cause: Sunlight hitting exposed curd
What to do: Blanch self-blanching types by tying outer leaves over the curd, or choose a self-wrapping variety.
Loose, grainy curd texture
Likely cause: Heat stress or delayed harvest
What to do: Harvest promptly at firm maturity; grow as a fall crop where summers run hot.
Varieties worth growing
Snowball Y Improved
Classic self-blanching white head, dependable in home gardens.
Graffiti
Purple curd holds color when cooked and needs no blanching.
Veronica (Romanesco-type)
Lime-green spiraled curd; heat-tolerant compared to standard white types.
Growing cauliflower in containers
5-gallon pot minimum; needs steady fertility and moisture that containers make harder to maintain than a garden bed.
Nutrition
Sulforaphane, glucosinolates, vitamin K, calcium. Brassicas are the vegetable powerhouse.
Common questions
Do I need to tie the leaves over the head?
Only for white varieties that aren't self-blanching. Purple, green, and orange types generally don't need it since sun exposure doesn't discolor them the same way.
Why is cauliflower harder to grow than broccoli?
It has a narrower window of ideal temperature (60-65°F) for curd formation and is less forgiving of heat or cold stress, which produces buttoning or ricey curds.
Where these numbers come from
- USDA Plant Hardiness Zone Map (2023 revision). Zone assignment and the 30-year normals behind every cold-hardiness figure.
- NOAA NCEI 1991-2020 Climate Normals. Frost dates, growing-season length, and the probability bands on both.
- Cornell, UMN, and UC Davis Cooperative Extension crop guides. Spacing, days to maturity, soil pH targets, and per-plant yield ranges.
- USDA FSIS / FDA Produce Safety guidance. Wash, cure, and cold-storage handling numbers.
Ranges are regional guidance, not a promise for your yard. Your own logged results always override the published range.