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Sweet Potatoes are tropical vegetables and thrive in the long, hot summers of the South, but they can be grown wherever they will have 150 frost-free days to develop. Once planted, sweet potatoes will produce their nutritious, flavorful roots with little care.

1. Select a SweetPotato Variety

There are two types of Sweet Potatoes: dry-fleshed and moist-fleshed. Popular moist-fleshed varieties include Beauregard, Hernandez, Jewel, Carolina Ruby, Cordner, Porto Rico 198, and White Delight. There are currently no dry-fleshed varieties for which seed roots and plants are available in North Carolina. For a more complete comparison of Sweet Potato varieties click here for the Sweet Potato Variety Description Table.

2. Start Your Sprouts

Start your sprouts a month before warm weather takes hold, when night temperatures get no colder than 60 degrees.

• A) Suspend a Sweet Potato on toothpicks in a container and cover half of the Sweet Potato with water. This will produce several sprouts. Larger quantities can be grown by placing several Sweet Potatoes on a bed of sand and covering them with a 2-inch layer of moist sandy soil.
  

• B) If starting your own sprouts isn’t feasible, buy them at a garden center or from NC Certified Seed Growers.

In about a month, the sprouts will grow 8-10 inches, which is the optimum length for transplanting to the garden, and will bear several leaves. Remove the sprouts for planting by giving them a twist or cutting them off with a knife.

3. Transplant Your Sprouts

With sprouts in hand, you’re now ready to plant. Sweet Potatoes do best in well-drained, sandy, loamy soil. Light, loamy soils usually result in roots with better shapes than those grown in heavy or clay soils.

• A) Prepare the soil by tilling well and applying an 8-8-8 fertilizer at the rate of 2 pounds per 25 feet of row. Push the softened, fertilized soil into a foot-wide, flat-topped ridge row that is 8 inches high.
  

• B) Plant sprouts 9 to 10 inches apart in the center of the ridge row and at a depth of 3 inches with at least 2 plant nodes underground and 2 or more leaves above ground. Immediately after transplanting, water well.
  

Fertilizing: Roots will begin to form in 30 to 45 days and need nitrogen, phosphorus, and potash for optimum growth. Thirty days after transplanting sidedress, place fertilizer 2-3 inches to the side of the plant, with an 8-8-8 fertilizer at the rate of 2 pounds per 25 feet of row.

Insect Control: Be sure to follow all label directions, restrictions, and precautions. Use a foliar spray of Sevin or Malathion at the rate of 2 tablespoons per gallon of water every 7 to 14 days as necessary.

Weed Control: A bit of weeding, done carefully so as not to injure the shallow roots, is usually all that is needed. Uncontrolled weeds can decrease Sweet Potato yields as much as 100%.

4. Harvest Your Sweet Potatoes

Harvesting of Sweet Potato roots is usually done between 90-120 days after transplanting or as soon as possible after a frost has blackened the tops of the plants

• A) Check roots for maturity. A mature Sweet Potato will have 4 to 5 roots of varying sizes, but the majority should have a 1 3/4 inch diameter and be 3-9 inches in length. You can check for maturity by gently lifting the Sweet Potatoes out of the ground with a shovel making sure they do not become detached from the vine. If not mature, lower back down and cover with soil.
  

• B) Dig Sweet Potatoes carefully because their skin is thin and they will bruise easily. It is best to wear gloves when handling them. Do not leave the roots exposed to direct sunlight with temperatures above 90 degrees for more than 30 minutes because they will sunscald and be more susceptible to storage rots.
  

• C) Once the Sweet Potato roots have been removed from the garden, spread them out to dry for several hours away from direct sunlight. Once dry, put them in newspaper-lined boxes and leave them in a dry, ventilated area for 2 weeks for curing. Once cured, store in a cool, dry place (50-55 degrees) until you’re ready to cook them

Sweet Potatoes can be stored for up to 10 months with little reduction in quality.