Cauliflower is ready to harvest 70 to 90 days after sowing seed.
Plant cauliflower so it comes to harvest in a cool part of the year; the optimal growing temperatures for cauliflower are the mid 60°sF (15°+C).
Plant cauliflower in early spring for harvest before summer heat or plant in late summer for fall harvest. In mild-winter regions, plant in the fall for spring harvest.
When to Harvest Cauliflower
- Harvest cauliflower when heads are 6 to 8 inches (15-20 cm) in diameter but still compact and smooth.
- The cauliflower head is a collection of flower buds; harvest the head while it is white and before yellow buds start to open. Cauliflower loses its flavor and texture when buds loosen.
- When curds begin to loosen, separate, and open, harvest immediately. When curds fully loosen, the head is called “ricey” and is not good for eating.
Blanching Cauliflower Before Harvest
- When heads are 2 to 3 inches (5-7 cm) in diameter—about the size of an egg, lift the outer leaves up over the head and tie them together with a piece of twine; this will blanch the head—ensuring that it is white at harvest. When heads are blanched pure white they are ready for harvest.
- From the time you tie the leaves and begin the blanching process, cauliflower heads (also called “curds” and “buttons”) will be ready for harvest in about 4 days if the weather is warm and about 10 days if the weather is cool.
- Check heads daily to make sure they are smooth, tight, and hard.
- Let the heads continue to grow as long as they stay compact; an ideal head will be 6 to 8 inches (15-20 cm) across.
How to Harvest Cauliflower
- Cut heads with a sharp knife leaving about 3 inches of stem to keep the florets intact. Keep enough wrapper leaves also intact to hold the head together.
- A cauliflower plant produces one head and then it is done.
How to Store Cauliflower
Store cauliflower in a cold and moist place, 32°-40°F (0°-4°C) and 95 percent relative humidity. Cold and moist storage can be a challenge. Refrigerators provide the cold, but they also dry the air.
- Wrap unwashed cauliflower in a damp cloth or paper towel and put it in a perforated plastic bag in the vegetable crisper drawer of the refrigerator; this will maintain humidity.
- Cauliflower will keep in the refrigerator for two to four weeks.
- Stored cauliflower gives off a strong odor. As an alternative to keeping cauliflower in the refrigerator, you can store it in a cold location—at just above 32°F (0°C)—such as a root cellar, basement, shed, or garage.
- Cauliflower stored below 32°F will discolor and the stem will become hollow. Cauliflower stored at low humidity levels will turn brown.
- Cauliflower can be frozen shortly after harvest. Break the head into 1-inch chunks and soak them for 30 minutes in a gallon of water with a tablespoon of salt added (to kill any insects), blanch for 3 minutes, rinse, drain and then freeze.
More tips at How to Grow Cauliflower.