Cauliflower (Brassica oleracea) is a cool-season vegetable that requires its growth cycle to align perfectly with moderate temperatures. Successful cultivation depends entirely on temperature consistency, requiring sustained cool weather, ideally between 60°F and 70°F, for the head—known as the curd—to form properly. Because Texas spans multiple climate zones, a single planting calendar is not practical for the entire state. Timing must be precisely adjusted to ensure plants mature before the onset of intense summer heat or a harsh winter freeze.
Defining Texas Growing Regions
Due to vast differences in climate and geography, Texas is best divided into three general growing regions for cool-season crops like cauliflower. Each region faces unique temperature challenges.
The Northern region, including the Panhandle, has the shortest growing season and coldest winters, requiring timing to avoid hard freezes. Central Texas, which includes the Hill Country, benefits from two distinct growing seasons. However, sudden temperature spikes risk causing the cauliflower to “button,” or form a small, premature head. The South Texas and Gulf Coast regions have the mildest winters, allowing for the longest growing window, but face the challenge of persistent, intense heat that starts early.
Detailed Planting Timelines by Region
The fall growing season is the most reliable time to plant cauliflower in Texas, as plants benefit from cooling temperatures as they mature. Starting with transplants, which are seedlings grown indoors for four to six weeks, is recommended to bypass the slow germination phase and increase survivability.
In North Texas and the Panhandle, transplants should be moved outdoors in mid-August to early September to ensure maturity before the first killing frost. For a spring crop, start seeds indoors in January for transplanting in late February or early March, aiming to harvest before temperatures consistently exceed 80°F.
Central Texas gardeners can transplant for a fall harvest from late August through September. For a spring crop, transplants can go into the garden from late January to mid-March, taking advantage of the Hill Country’s longer moderate season.
The warmest regions of South Texas and the Gulf Coast offer the greatest flexibility, often allowing for a winter harvest. Transplants can be set out as late as October or early November for a winter crop, or from January through mid-March for a spring harvest. Gardeners here have the best chance for successful spring crops, provided they utilize heat-tolerant varieties.
Site Preparation and Ongoing Care
Before planting, the chosen site requires preparation to meet the specific needs of cauliflower. The soil must be rich in organic matter and well-draining, as the plant needs consistent moisture but will not tolerate soggy roots. Incorporating aged compost before planting helps maintain uniform moisture and nutrient supply, which is necessary to prevent the formation of small, underdeveloped heads.
Cauliflower requires full sunlight, meaning at least six to eight hours of direct sun daily. The plant is a heavy feeder, especially of nitrogen, and benefits from a balanced fertilizer application at transplanting and again as the head begins to form. Consistent watering is important during curd development, as moisture stress can trigger premature maturity.
For many white cauliflower varieties, blanching is necessary to keep the head bright white. When the developing curd reaches the size of a tennis ball, the outer leaves should be gently gathered and tied loosely over the head. This shading prevents sun exposure, which causes discoloration, browning, or a bitter flavor.
Knowing When to Harvest
The curd should be ready for harvest when it is compact, feels firm to the touch, and has reached six to eight inches in diameter. The individual floret clusters must still be tightly grouped together; separation indicates the plant is over-mature and may taste coarse or bitter.
Once the head is ready, use a sharp knife to cut the main stem beneath the curd. Leave a few of the protective wrapper leaves attached to the harvested head. These remaining leaves help shield the curd from bruising and prolong its quality. Freshly harvested cauliflower can be stored in the refrigerator for about a week.