Planting, Growing, and Harvesting Cauliflower
Cauliflower is a sun-loving, cool-season crop to grow in spring and fall. An annual plant in the Brassica family, cauliflower’s edible white flesh is extremely healthy and considered a “superfood.”
This vegetable’s name comes from the Latin words caulis, for cabbage, and floris, for flower. It’s a descendent of wild cabbage! Like its cousin broccoli, the tightly bunched florets of cauliflower are connected by a thick core, often with a few light leaves surrounding it.
Though usually white, cauliflower does come in other colors including purple, yellow, and orange. No matter the color, the taste is the same: mild, slightly sweet, a little nutty.
Cauliflower can be a challenge for the beginner gardeners because it requires consistently cool temperatures with temperatures in the 60°Fs. Otherwise, it may prematurely “button”—form small, button-size heads—rather than forming a single, large head.
- Soil needs to be very rich in organic matter; mix aged maure and/or compost inot the bed.
- Cauliflower also needs extra nutrients. Apply 5-10-10 fertlizer. Fertile soil holds in moisture to prevent heads from “buttoning.”
- It is best to start cauliflower from small nursery plants versus sowing seeds.
- If you seed, start 4 to 5 weeks before the last spring frost date. Sow in rows 3 to 6 inches apart and up to 1/2 of an inch deep. Water consistently during germination and growth.
- Transplant seedlings (or small nursery plants) 2 to 4 weeks before the last spring frost date, no sooner and not much later.
- Set plants 18 to 24 inches apart with 30 inches between rows.
- In early spring, be ready to protect plants from frost by covering them with old milk jugs, if necessary. Extreme cold can halt growth and/or form buttons.
- Plant a fall crop 6 to 8 weeks before the first fall frost date but after daytime temperatures are regularly below 75°F. Shade plants from heat, if necessary.
- Add mulch to conserve moisture.
- Cauliflower dislikes any interuption to its growth. Change, in the form of temperature, moisture, soil nutrition, or insects, can cause the plants to develop a head prematurely or ruin an existing one.
- Water regularly with 2 inches of water each week; even with normal rainfall, this usually requires supplemental watering.
- For best growth, side-dress the plants with a high-nitrogen fertilizer 3 t o 4 weeks after transplanting.
- Note that the cauliflower will start out as a loose head and that it takes time for the head to fully form. Many varieties take at least 75 to 85 days from transplant. Be patient!
- When the curd (the white head) is 2 to 3 inches in diameter, blanch it: Tie the outer leaves together over the head and secure with a rubber band, tape, or twine to keep light out. (This is not necessary for self-blanching or colored varieties). The plants are usually ready for harvest 7 to 12 days after blanching.
- Brown heads indicate a boron deficiency in the soil. Drench with 1 tablespoon of borax in 1 gallon of water. (Avoid getting boron on other plants.) Or, provide liquid seaweed extract immediately; repeat every 2 weeks until symptoms disappear. In the future, add more compost to the soil.
- For white varieties, pink heds can indicate too much sun exposure or temperature fluctuations. Purple hues can be due to stress or low soil fertility.
- ‘Graffiti’: purple; tends to be milder and sweeter than the white varieties.
- ‘Snowball’: smooth, white, medium 6-inch heads; a good yield throughout the growing season.
- ‘Orange’ varieties, such as ‘Cheddar” and “Flame Star’, are creamier and sweeter than white varieties with more vitamin A.
Cauliflower at a farm stand in Washington, D.C., 2019. Credit: Wendy Hagen.
- Plants are usually ready to harvest in about 50 to 100 days, depending on variety, or 7 to 12 days after blanching.
- When the heads are compact, white, and firm, then it is time to harvest them. Ideally, the heads will grow to 6 to 8 inches in diameter.
- Cut the heads off the plant with a large knife. Be sure to leave some of the leaves around the head to keep it protected.
- If the heads are too small, but have already started to open up, they will not improve and should be harvested immediately.
- If the cauliflower has a coarse appearance, it is past maturity and should be tossed.
- Store heads in a plastic bag in the refrigerator. They should last for about a week.
- For long-term storage, you can also freeze or pickle the heads. To freeze, cut into 1-inch-bite pieces. Blanch for 3 minutes in lightly salted water. Cool in an ice bath for 3 minutes, drain, and package. Seal and freeze.
Cauliflower is nothing but cabbage with a college education.
-Mark Twain (1835-1910)