Freedom F1

Cauliflower (Brassica oleracea var. botrytis)

Cauliflower is a cool-season crop closely related to broccoli, cabbage, kale, turnips, and mustard. Unlike many of its relatives, cauliflower has more demanding climatic needs, performing best in cool, moist conditions. The plant is highly sensitive to stress from extreme heat, drought, or freezing temperatures, which can cause it to produce small, underdeveloped heads known as "buttons."

Grown for its edible head, often called a "curd" due to its resemblance to cheese curds, cauliflower is most commonly white. However, some varieties feature striking colors like purple, orange, or green, adding diversity to this versatile vegetable.

Soil

Cauliflower thrives in well-drained, fertile soil rich in organic matter, with a pH range of 6.0 to 7.5. Consistent moisture is essential throughout the growing season, so regular irrigation is recommended for optimal growth. This crop does not tolerate hot weather well, making it most successful when planted for spring or fall harvests. Raised beds or ridges can improve drainage in heavy soils. Avoid planting cauliflower in fields where cole crops have been grown within the last 3 years to reduce the risk of disease.

Temperature

Cauliflower grows best at daytime temperatures between 60°F and 75°F, with nighttime temperatures between 50°F and 60°F. If temperatures exceed 80°F or fall below 40°F, growth may be stunted. Exposure to temperatures below 50°F for more than 7 consecutive days can cause "buttoning," where plants produce small, premature heads.

Planting & Spacing

Transplanting:

• Sow seeds 4 to 6 weeks before transplanting using one of the following methods:
• Plug flats: Place 2–3 seeds per cell in 72-cell flats.
• Row flats: Sow 3–4 seeds per inch in 20-row flats, 1/4–1/2” deep.
• Maintain soil temperatures above 70°F for germination, then reduce to 60°F.
• Once seedlings develop their first true leaves, thin them to one plant per cell.
• Transplant seedlings when they are 4–6 inches tall (4–5 weeks old).
• Space plants 15–18 inches apart in rows 24–36 inches apart.
• Wider spacing improves air circulation and reduces disease pressure.

Direct Seeding:

• Sow seeds 1/2” deep, 3 seeds every 18 inches in rows 24–36 inches apart.
• Thin to 1 plant every 18 inches when the first true leaves have formed.
• Direct seeding is less common than transplanting but can be used successfully in areas with mild weather.

Blanching

Blanching heads is beneficial for many varieties in hot weather. Take the wrapper leaves and pull them over the heads, then secure with twine when the heads are about the size of a baseball. Cracking the midribs of the leaves and folding over the head is another method. Certain varieties have self-wrapping leaves and may not need blanching.

Harvest

Cut mature heads that are compact, white in color, and roughly 6 inches. Be sure to leave at least one set of leaves to protect the curds. For consistent quality, harvest heads when they reach the desired market size before they become loose or discolored.

For more information, please see links below:

• Oklahoma State - Cole Crop Production
• Oregon State - Cauliflower Production
• University of Kentucky - Cauliflower Guide

Note: This information is summarized. Additional details and expanded guidelines can be found in our production sheets available in the Holmes Seed Grower's Guidebook.

Downloadable Copy:

• Please click here to download a printable version (Page 1).
• Please click here to download a printable version (Page 2).