Some varieties of sweet potatoes are those pretty ornamentals, but the edible ones produce the healthy vegetable we’ve all come to love. Given enough room, you can easily grow them here in north Texas with the help of this project list from North Haven Gardens.
- Compost – Try Vital Earth Organic Compost or Acidified Compost for amending native soil. Sweet potatoes must have very loose soil in order to develop well.
- Mulch – Very important for this crop, a good mulch will even out moisture levels, keep soil cooler, and control weeds. Try a 2 to 3-inch layer of pine straw mulch.
- Fertilizer – Organic fertilizers such as Espoma Garden-tone ensures better production and supplies trace nutrients, increasing the flavor and plant health.
- Texas Green Sand – Adding in this naturally-mined sand can raise potassium and iron levels, which is ideal for sweet potatoes.
TIMING: The soil must have become consistently warm, around mid-April to mid-May, in order to plant the potatoes successfully. Heat will not be a problem, but plants will not take temperatures less than 55 degrees.
SELECTION: NHG offers several varieties. A ’bush’ type will take up slightly less room than ’vining’ types. Plus, some will have the more common orange flesh, while others yellow, but all will do well. You’ll make your selection from a small plant, called a slip. Keep these covered with moist soil or sand until time to plant.
SITE: Select a site that receives 6 or more hours of direct sunlight. Make sure your sweet potatoes have plenty of room to grow, as vines will become large and sprawl.
- In a container, use our soil mix recipe (from our Vegetable Project List handout) or use Mayer Materials Raised Bed Mix for raised beds. Use a 20 to 24″ container that drains freely: Sweet potatoes need consistent moisture and loose, well drained soil. Planting in raised beds is always a good option.
PREP: Sweet potatoes really appreciate a well-drained, sandy loam soil with a slightly acid pH. Incorporating acidified compost can help increase the acidity.
- First incorporate the fertilizer in the entire bed or row to be planted at time of planting. With fertile soil, additional feeding is not needed for sweet potatoes.
PLANT: Get the slips planted as soon as possible after purchase. Place roots in the ground and plant about halfway up the stem, 3 to 4″ deep. Set slips about 2 feet apart in the garden. Water the slips well at planting time.
- Mulch the plantings to protect the soil and keep the vines from rooting.
- Continue to water carefully to establish the young plants, as they can be quite sensitive to wilting. They are more drought tolerant once established, but may wilt temporarily simply due to higher temperatures. Do not overwater them.
- After 2 months of growth, make sure the soil around the plants stays evenly moist and weed-free until vines cover the area.
- Sweet potatoes mature 90-120 days after planting. Stop watering 2 to 3 weeks before harvest. Check the size of the tubers by carefully removing soil from around the root. Tubers are ready when about 6″ long. You can choose to store them in the soil, or begin to harvest them.
- Leave tubers in the soil until needed, or when the soil is dry, carefully dig tubers with a large fork or shovel—or by hand, as the skin of freshly dug sweet potatoes is very delicate. Handle them with care, avoiding any nicks and scrapes.
- Dry freshly dug sweet potatoes outdoors in the shade for several hours. Do not wash off soil. Place tubers in a basket or crate and cure by keeping at room temperature and dry, but with high humidity, such as a laundry room. Stored in a dry spot at 55 degrees, they can keep for up to 3 months.