Cauliflower

Brassica oleracea var. botrytis · Cabbage family (Brassicaceae)

At a glance
Hardiness zones	2 to 11
Sun	full sun
Water	moderate
Life cycle	annual
Frost	Half-hardy: takes a light frost
Soil pH	6.0–7.0
Spacing	18 to 24 inches
Days to harvest	50 to 80 days
Soil temperature to plant	at least 40°F

About Cauliflower

Cauliflower is a cabbage-family crop grown for its dense white (or orange, green or purple) head of flower buds. It is fussier than its relatives: it needs steady moisture and mild temperatures, but a well-timed crop is a real treat.

Grown as a cool-season annual in every zone; time it for the cool weather of spring or fall. It is more sensitive to cold than cabbage, and hot nights (above about 77F) can keep heads from forming.

When to plant

Timing is counted from your average last spring frost (and first fall frost). Sow & Tell works out the actual dates for your ZIP code.

Start seeds indoors: 4 to 8 weeks before the last frost
Set out plants: up to 2 weeks before the last frost
Fall planting: 9 to 10 weeks before the first fall frost

Days count from setting out transplants: about 50 to 60 for spring varieties and up to 80 for fall ones. Start seed indoors 4 to 6 weeks before transplanting; the fall number is for setting out transplants started in early summer.

Soil

Rich, moist, well-drained loam; plants should never dry out, so water about an inch a week.

Use rich, well-drained soil with compost or well-rotted manure and follow a soil test; without one, about 3 lb of 5-10-10 per 100 sq ft before planting, with soil pH about 5.8 to 6.5.

Feeding

3 to 4 weeks after transplanting, once plants are established: nitrogen fertilizer such as calcium nitrate (15.5-0-0) or 33-0-0. Use about 2 lb of calcium nitrate or 1 lb of 33-0-0 per 100 ft of row, beside the plants, and water it in.

If you worked in plenty of manure or compost you may need less fertilizer; skip extra phosphorus unless a soil test calls for it.

Harvest

For white types, tie the outer leaves over the head once 2 to 3 inches of curd shows, then cut the head 7 to 12 days later when it is about 6 to 8 inches across, firm and tight. Pick before the curd turns loose and grainy ('ricey'); colored types are not tied.

Cut the head once when it is about 6 to 8 inches across, firm and tight; the plant is then done.

Varieties (24)

Variety	Type	Days	Notes
Flame Star	Orange	62 to 80 days	Yellow-orange heads. Mississippi State notes high yields.
Cheddar	Orange, hybrid	58 days	Firm, medium-weight orange heads with more beta-carotene than white cauliflower.
Purple Moon	Purple	62 days	A purple cauliflower on the Central Texas variety list.
Graffiti	Purple, hybrid	80 days	Purple heads colored by anthocyanin pigment. The plant is large, vigorous and open, with smooth, domed heads.
Violet Queen	Purple, hybrid	65 days	Purple curds on a tall, upright plant.
Puntoverde	Romanesco (green)	78 days	Strong, rugged plants. Mississippi State says it does better than typical Romanesco types.
Veronica	Romanesco (green)	78 days	Slightly nutty. A green Romanesco type with pointed, spiraling peaks.
Absolute	White	90 days	Very white curds on an upright plant.
Aerospace	White	65 days	Dense, uniform heads with a dome shape.
Amazing	White	65 to 68 days	A white cauliflower that Utah State rates excellent for yield and eating quality.
Denali	White	80 days	A white cauliflower Utah State recommends for fall harvest.
Early Snowball	White	52 days	An early white type with large, smooth heads.
Snowball Y	White	60 to 68 days	A standard white type with deep, very solid, smooth heads. It matures later than Snowball X.
Symphony	White		A vigorous, upright, early plant with dense, white, domed heads.
White Contessa	White	65 days	A heat-tolerant white type that Utah State rates excellent for yield and eating quality.
White Magic	White		An extra-large, upright plant with heavy white domed heads that are well covered by leaves.
Candid Charm	White, hybrid	75 days	A uniform, vigorous hybrid with a tight, domed head. It matures later than Snowball Y.
Early Glacier	White, hybrid	50 to 55 days	An early hybrid. Wisconsin lists it at 50 to 55 days from transplanting.
Early White Hybrid	White, hybrid		A very early hybrid with large, round heads that hold well without turning loose or grainy.
Fremont	White, hybrid		A hybrid on Kansas State's recommended list.
Majestic	White, hybrid	66 days	A vigorous hybrid with a heavy, domed head. Kentucky lists resistance to black rot and downy mildew.
Snow Crown	White, hybrid	50 to 68 days	An early white cauliflower on a medium-size plant with a half-domed head. It does well in early summer or fall.
Snow King	White, hybrid		A white hybrid on Wisconsin Extension's variety lists.
Self-Blanche	White, self-blanching	60 to 68 days	Leaves next to the head wrap over it and shade it, so the curd stays white with less work. The wrapping works best in cool weather.

Good neighbors

Arugula, Mustard greens

UMN Extension says arugula and mustard can work as trap crops that draw flea beetles away from cabbage-family plants, and mixes of three or more species work better than one; this is a pest-trapping tactic, not a guarantee.

Pests to watch for

Flea beetles, Imported cabbageworm, Cabbage looper, Diamondback moth, Cabbage maggot, Swede midge, Bagrada bug, Beet armyworm, Voles

Diseases and problems

Black rot of cabbage-family crops, Clubroot, Downy mildew, Edema (oedema), Transplant shock, Bolting (going to seed), Boron deficiency, Tipburn, Alternaria leaf spot (cabbage family), Verticillium wilt, White mold, White rust, Turnip mosaic

In the kitchen

Roasted, steamed, mashed, riced or eaten raw with dips.

Keeping it: Keep heads in a plastic bag in the refrigerator for up to a week; very cold, humid storage stretches that to about 3 weeks.

Pets: Not listed as toxic by the ASPCA

Sources

Photo: Photo: Coyau / Wikimedia Commons, CC BY-SA 3.0 (CC BY-SA 3.0). Photo resized for the web.

Planting dates and advice are general guidance; check with your local Cooperative Extension office for your area.