Spring Growing Guides
Cauliflower Growing Guide
|Seed Depth||Seed Spacing||Soil Temp for Germ.||Days to Germ.||Thin Plants To||Approximately 60-85 seeds per 1/4 gram.|
Brassica oleracea, Botrytis Group
This nutritious, hearty food is an excellent source of vitamin C, vitamin K, and folate. Steamed and mashed it makes a low-calorie, low-carb mashed potato substitute. Thanks to our extensive trialing, we've chosen superb cauliflower varieties for spring and fall harvest. With the addition of overwintering types, you'll have a nearly seamless supply of fresh-from-the-garden crops from fall to the following spring in milder climate gardens.
CULTURE: Best started indoors as transplants. Start early varieties from mid-March through June, and autumn and overwinter varieties in May and June. Sow into sterile seedling mix. Keep the seedlings moist, and provide adequate nutrition with a balanced fertilizer. See our Natural Fertilizer section. Transplant out at 6 weeks when there are 6-8 true leaves and after the danger of a hard frost. Stressed seedlings can lead to small heads or premature bolting. Transplant into soil rich in humus or compost that has been adjusted to a pH of 6.5-7. Space transplants 18-36 inches between rows. For best results, dig 1/4-1/2 cup of our complete fertilizer into the soil around each plant. Water evenly and thoroughly for a good crop. Too much nitrogen or a boron deficiency can cause hollow stem. Periodic soil tests can be very helpful in diagnosing problems.
TO DIRECT SOW: Cauliflower can be directly seeded from April through June. Sow the seed in rows 18-36 inches apart. Cover the seed with loose soil or sifted compost. Keep the seedbed uniformly moist as rough heads or leaves in the head are usually from heat-stressed seedlings. Thin plants and work in 1/4-1/2 cup of our complete fertilizer or equivalent around the base of each plant.
INSECTS: See Brassica Insect Information below.
DISEASE: The common disease problems of cauliflower are similar to broccoli. Many disease and insect problems can be reduced if cole crops can be grown in a 4-5 year rotation with non-cruciferous crops.
BLANCHING: Many of our varieties tend to self-wrap. To obtain completely white heads, especially from spring-sown varieties, tie the inner leaves around the curd when it starts to form, or break over some inside leaves so they lie flat to shade the head.
HARVEST: When mature, the flowerets just begin to separate and appear slightly ricey. At this point, the flavor is still at peak quality and the size is maximum. Store at 34°F and 95% relative humidity.
SEED SPECS: Minimum germination standard: 75%. Days to maturity are calculated from date of transplant. Add 25-35 days if direct seeding. Usual seed life: 3 years.
Brassica Insect Information
Aphids: Control aphids with a hard spray of water, Azatrol or Pyrethrin. Also, select varieties that mature later in the season when aphid populations decline.
Cabbage worms, loopers, and root maggots: The first sign of cabbage worms will be white diamond-back moths fluttering near the plants. They lay eggs in the soil, which hatch into worms that can cause severe root and head damage. To control light infestations, spray plants with Bacillus thuringiensis (BT). For heavy infestations, bait cabbage worms by mixing wheat bran into a BT solution. Add 1 tablespoon of molasses. Broadcast the bran mixture around the base of plants. Reapply as necessary. Using Reemay or Grow Guard 20 can also provide control.
Flea beetles: Flea beetles chew tiny pinholes in leaves. Early control is essential to minimize the damage. Spray young plants with Pyrethrin every 2 days. Using floating row covers such as Summer Insect Barrier can also provide control.
Symphylans: In some areas of the US, symphylans (also known as garden centipede) can severely retard the plant growth of cole crops. Only 1/4 inch long, white, and very active, they eat the root hairs of developing plants. Contact your local county extension agent if you suspect you have a problem.