Light requirements: Full sun.
Planting: Space 12 to 18 inches apart.
Soil requirements: Sweet potatoes need well-drained soil that’s not too rich. Work 1 inch of compost or other organic matter into soil prior to planting. Tubers develop best in loose, sandy soil. Build raised beds in heavy clay soil. Soil pH should be 5.8 to 6.2.
Water requirements: Water plants weekly to keep soil consistently moist.
Frost-fighting plan: Sweet potatoes are very sensitive to frost. Light frosts (28º F to 32º F) damage leaves and can cause roots to rot. Protect newly planted seedlings from late spring frosts by covering plants with straw or a frost blanket.
Common issues: A soil-borne fungal disease called scurf can devastate sweet potatoes. You can avoid it by always planting certified, disease-free plants such as these sold by Bonnie. Watch out for Japanese beetles and other leaf-eating insects, sweet potato weevils, wireworms, and nematodes. Keep deer from nibbling leaves with floating row covers or bird netting.
Harvesting: Potatoes are usually ready as the ends of vines begin to turn yellow or just before frost. Harvest before frost; cool temperatures can reduce tuber quality and storage. To harvest, find the primary crown of the plant you want to dig, and use a digging fork to loosen an 18-inch wide circle around the plant. Pull up the crown and use your hands to gather sweet potatoes. Cut vines out of your way before digging. Cure tubers to develop sweetness by lightly brushing off soil, laying unwashed tubers in a warm (80°F to 90°F), well-ventilated place for about 10 days.
Storage: Store sweet potatoes in a cool, dry spot. Do not refrigerate or store below 50°F. Cured sweet potatoes keep up to 6 months when stored around 60°F with high humidity. A basement is ideal, though an air-conditioned storage room or pantry works, too.
For more information, visit the Sweet Potatoes page in our How to Grow section.
