Cabbage is a cool-season biennial crop, but it is treated as an annual, focusing on harvesting the dense head of leaves within one season. This member of the Brassica oleracea family thrives in mild conditions, ideally when temperatures range between 60 and 65 degrees Fahrenheit. Success in Tennessee depends on precise timing, as the state’s climate features narrow windows between the last frost and the onset of intense summer heat. Planting must be scheduled so the crop matures before daytime temperatures consistently exceed 80 degrees Fahrenheit, which causes the plant to struggle or “bolt.”
Spring Planting Schedule in Tennessee
The spring planting season requires starting seeds indoors to get a head start on the brief cool weather period. Seeds should be sown approximately six to eight weeks before the last expected spring frost date in the region. In Tennessee, preparation typically begins in late January or early February. Providing supplemental light and maintaining a consistent temperature around 70 degrees Fahrenheit encourages strong, stocky seedlings.
Transplanting these hardened-off seedlings into the garden should occur in early to mid-spring, generally from March through mid-April. This timing often places transplanting approximately four weeks before the final frost, which the cold-tolerant plants can handle. The goal of this spring crop is to ensure the cabbage heads are ready for harvest before the hot days of late May and June arrive. An early variety that matures quickly is the best choice for a spring planting to beat the heat.
Fall Planting Schedule in Tennessee
The fall season is the most favorable time for growing cabbage in Tennessee, as heads mature during cooling weather, which enhances sweetness. Starting seeds for a fall harvest must happen in the middle of summer, a challenging period due to the heat. Seeds should be sown indoors between early July and mid-August, with the date depending on the variety’s days to maturity.
The primary challenge is ensuring seedlings survive the heat stress of late summer after transplanting. The ideal window for moving young plants outdoors is from late August through September. This schedule allows plants to establish roots during late summer, ensuring heads form and mature as cooler weather arrives in October and November. Careful management of soil moisture and providing temporary afternoon shade improves the success rate of these transplants.
Essential Soil and Site Preparation
Cabbage plants are heavy feeders that require a planting site that receives a minimum of six hours of direct sunlight each day for proper head formation. The soil must be fertile, moisture-retentive, and well-draining to prevent root diseases. Before planting, the soil needs substantial amendment with organic matter, such as well-rotted compost or manure, to improve structure and fertility.
Cabbage prefers a soil pH that is slightly acidic to neutral, ideally ranging between 6.0 and 7.0, with 6.5 to 6.8 being optimal. This pH range is important for nutrient availability and to discourage the development of clubroot, a soil-borne disease common to the cabbage family. Incorporating a complete, balanced granular fertilizer, such as a 10-10-10 or 8-16-16 formula, into the soil two weeks before transplanting provides the necessary initial nutrients. Before moving seedlings outdoors, they must undergo a hardening-off process, which involves gradually exposing them to outdoor sun, wind, and temperatures over seven to ten days.
Post-Planting Care and Harvest
Once transplanted, cabbage requires consistent and regular watering to maintain even soil moisture, with the goal being about one to two inches of water per week. Fluctuations in moisture, particularly from dry periods followed by heavy watering, can lead to the heads splitting prematurely. Applying a layer of organic mulch around the plants helps to regulate soil temperature and conserve moisture, leading to steady growth.
Cabbage demands a high level of nitrogen for the vigorous leaf growth required to form a dense head. About two to three weeks after transplanting, a light side-dressing of a nitrogen-rich fertilizer should be applied around the base of the plants. Once the heads begin to form and firm up, all fertilization should cease, as continued feeding can contribute to head splitting.
Common pests in Tennessee, like the green cabbage worms and cabbage loopers, are manageable with protective measures such as lightweight floating row covers installed immediately after transplanting. Cabbage heads are ready for harvest when they feel solid and dense, indicating a compact internal structure. The proper technique is to use a sharp knife to cut the head at its base, leaving the outer leaves and stem in place, which sometimes encourages a second, smaller head to grow.