QUESTION: Can I start cauliflower from seeds? How do you transplant cauliflower? -Sal R.
ANSWER: Like most cool weather crops, cauliflower (Brassica oleracea) thrives where a strong maritime influence keeps daytime temperatures around 70 degrees Fahrenheit. It starts reliably from seeds, which are sown indoors approximately four to six weeks before the last spring frost. In coastal areas with very mild summers, cauliflower can also be started in July and transplanted in early August. Once established, cauliflower seedlings transplant well and will grow quickly under suitably cool, moist conditions. However, they must be hardened off before transplant to help prevent stress, which can result in premature heading or stunted irregular growth.
Place the young cauliflower plants outdoors under light shade approximately one week before planting. Gradually acclimate them to direct sunlight until they can remain unshaded for eight hours without wilting.
Work the soil in a sunny or lightly shaded bed using a rotary tiller or a handheld cultivator. Break up the soil to a depth of 8 inches. Remove all weeds, stones, sticks and other debris from the soil.
Spread a 2- to 4-inch-thick layer of compost over the planting site. Sprinkle one-fifth cup of 10-10-10 ratio fertilizer for every 5 square feet of ground. Work the compost and fertilizer into the soil to a depth of 10 inches using a handheld cultivator.
Transplant the cauliflower plants on a cloudy or foggy day, or during the early evening hours. Space the planting holes 12 to 18 inches apart in rows 2 to 3 feet apart. Dig the holes just large enough to accommodate the roots without crowding them.
Position the cauliflower plants in the holes so the base of the stem sits just above the soil’s surface. Backfill around the roots and firm the soil. Water to a depth of 3 inches after planting to settle the soil and eliminate any trapped air.
Spread a 2-inch-thick layer of organic mulch, such as straw, around the base of each cauliflower plant to keep the soil cool and moist. Leave a slight gap between the base of the plant and the mulch layer to allow for some evaporation.
Water the cauliflower transplants to a depth of 2 inches at least once a week or whenever the top inch of soil dries out. Provide plenty of water, but do not saturate the soil since too much or too little water will result in stunted irregular heads.