Vegetable / Cool season
Cauliflower
The fussiest brassica, and worth one honest try
Plant out byApr 6zone 6
- Family
- Cabbage (Brassicaceae)
- Sun
- Full sun (6+ h)
- Difficulty
- Demanding
- Days to harvest
- 55-85 days
- Spacing
- 18 in apart, rows 30 in
- Pot size
- 5 gal pot (fine in pots)
- Frost
- Half-hardy
- Start
- Start indoors
- Water
When to plant
Showing .
Averages for a typical garden in the region. Your local frost dates may differ by 2-3 weeks, check a local source.Wait until Feb 16
In zone 6, start seeds indoors Feb 16 to Mar 23; plant out Mar 23 to Apr 6; sow again for fall Aug 11 to Sep 8. Average last frost Apr 20, first fall frost Oct 20.
Units
Of all the cabbage family, cauliflower is the one most likely to let you down. It wants weather around 60 to 65 degrees F, even moisture and regular feeding. Any hiccup, like a hot week, a cold snap, a dry spell or a root-bound transplant, can make it button. That means it forms a tiny head the size of a button and quits. Most failures trace back to some kind of stress.
Timing does most of the work. For spring, start seed indoors and set transplants out a few weeks before your last frost, so heads form before summer heat. In many areas fall is easier: plant in late summer, roughly six to ten weeks before first frost, and the heads fill in during cool autumn days. Clemson notes that ten days of 35 to 50 degree weather on a bigger plant can push it to bolt, so do not rush spring transplants out. Check with your local extension office for fall dates where you live.
When a head appears and reaches 2 to 3 inches across, pull the big outer leaves over it and tie them loosely. That keeps sun off the curds so they stay white. Self-blanching and colored types skip this step. Harvest about a week to twelve days later, while the curds are still tight. In a pot, give one plant at least 5 gallons and never let it dry out.
Things to consider
- Buy young transplants rather than big ones in crowded packs. Seedlings that sat root-bound are a common reason heads button early. Set them out while they are small and still growing fast, and water them in well.
- Cabbageworms, loopers and aphids hide under leaves and inside the head. Row cover from day one keeps the white butterflies from laying eggs. Lift it only to weed and check, then tuck the edges back down.
- Heads go past their best fast in warm weather. Once the curds start to loosen or look grainy, cut it, even if it seems small. A small tight head cooks better than a big loose one.
Good neighbours
Keep apart
Pests to watch for
CabbagewormsCabbage loopersAphidsFlea beetles
Questions about growing cauliflower
Why is my cauliflower head purple or pink?
On white types, a pink or purple tint usually comes from sun on the curds, temperature swings or stress. It is still fine to eat. Covering young heads with their leaves helps prevent it next time. Colored varieties are meant to look that way, so this only applies to white kinds.
Is fall or spring better for cauliflower?
For many gardens fall is more forgiving, because heads mature as days cool rather than heat up. Spring works where the warm-up is slow. Your local extension office can tell you which season growers near you favor. Whichever you pick, count back from the days to maturity on the seed packet.
Do I have to tie up the leaves?
Only for older white varieties. Self-blanching kinds curl their own leaves over the head, and orange, green or purple types need no shade. A clothespin or rubber band does it in about ten seconds per plant. Tie loosely so air moves and rain drains away from the head.
Save this crop
Pin it to a garden board so it is there when planting time comes round.
Similar crops
Sources
General guidance for home gardens. Frost dates are averages for a zone or region; check a local source (in the US your county extension office) for local timing.