Sweet potatoes thrive in the long, hot, and humid summers of East Texas, making the region a significant producer of this root vegetable. Successful cultivation depends entirely on precise timing, as this tropical plant requires specific warmth requirements for a healthy and abundant harvest. Knowing when to introduce the young plants, known as slips, ensures they receive the prolonged heat exposure necessary for proper tuber development.
Identifying the Ideal Planting Window
The requirement for planting sweet potatoes is ensuring the soil has reached and maintained a minimum temperature. Sweet potato slips will not establish properly until the soil temperature, measured at planting depth, is at least 65°F. For optimum growth, a soil temperature closer to 70°F is recommended. Planting too early in cool soil results in slow, stunted growth and a poor final yield, making a soil thermometer a more reliable guide than the calendar alone.
In East Texas (USDA Hardiness Zones 8b and 9a), this ideal soil temperature is typically achieved between mid-April and early June. The planting window begins after the danger of the last spring frost has completely passed, usually two weeks later than the last expected frost date. Gardeners should aim for a growing period of at least 100 to 150 frost-free days before the anticipated first fall frost. Varieties like ‘Beauregard,’ the most popular in Texas, require around 100 days to reach maturity. Planting within the ideal window ensures the slips benefit from the intense summer heat necessary for the development of large tubers.
Preparing the Planting Site and Slips
The sweet potato plant develops best in soil that is loose and well-drained, with a preference for a fine sandy loam texture. This lighter soil type allows the roots to expand easily without becoming misshapen or restricted. The soil should also maintain a slightly acidic pH range, ideally between 5.0 and 7.5.
Improving drainage and encouraging faster soil warming is accomplished by planting in mounded rows or raised beds. These structures should be built to a height of about 8 to 12 inches, which increases the depth of loose soil available for the developing roots. Excessive nitrogen fertilizer should be avoided, as it promotes vigorous vine and leaf growth at the expense of root production.
Sweet potatoes are grown from vegetative cuttings called slips. Whether slips are purchased or grown at home, they must be properly prepared before being transplanted. If the slips were grown in water, they should be hardened off by gradually exposing them to outdoor conditions for a few days to minimize transplant shock.
The Planting Process
Once the planting site is ready and the soil temperature is optimal, the slips are placed into the prepared mounds or rows. Proper spacing is necessary to allow for adequate air circulation and vine spread. Slips should be planted 12 to 18 inches apart within the row, with rows spaced 3 to 4 feet apart.
The slips are planted deep, burying the stem up to the base of the top set of leaves. This depth encourages the buried nodes along the stem to develop into the storage roots. Use a trowel or stick to create a diagonal hole in the side of the mound.
The slip is inserted, and the soil is then gently but firmly pressed around the base of the stem to eliminate any air pockets. Ensuring good soil-to-root contact is necessary for the slip to quickly begin taking up water and nutrients. Planting can be done effectively on an overcast day or in the late afternoon to reduce the stress of direct sunlight.
Initial Care After Planting
Immediately following planting, the sweet potato slips require a thorough and heavy watering. This settles the soil completely around the newly buried roots and stem, securing the plant in its new location.
For the first week or two after planting, consistent moisture is important until the slips show visible signs of establishment and new growth. While mature sweet potato plants are drought-tolerant, the young slips are highly sensitive to water stress during this initial period. Once established, the watering frequency can be reduced, as the plants are adapted to the hot Texas summers.
Early weed control is necessary in the first 40 days after transplanting, as the young slips cannot compete effectively for light, water, and nutrients. Monitoring the slips for early signs of pests, such as flea beetles, allows for quick intervention. Once the vines begin to spread and cover the soil, they naturally suppress most new weed growth.