Planting Sweet Potatoes
Plant sweet potatoes as soon as you receive the bare roots, or “slips”, in spring, after all danger of frost has passed.
Do not be concerned if the plants look limp and the green tops do not look healthy. If the roots are white and firm the plants are healthy and ready for planting. You can put them in a glass of water to help the roots absorb water and the greens should perk up.
Choose a sunny location with a loose, easily worked, well-drained soil. Sweet potatoes prefer a soil pH of 5.5 to 6.5. The ideal time to plant is late in the afternoon after the hottest part of the day, on a day that is not windy.
Plant sweet potatoes in ridges 8-12 inches high and 3 feet apart. Set the plants 10-18 inches apart.
When setting the plants in the ground do not cover the stem. Cover the roots and firm the soil. Water lightly.
If there is danger of frost cover the rows with row covers.
In areas with shorter seasons use black plastic mulches to warm the soil earlier in the season. If you use this method you may need to water more during periods of high heat during the growing season.
How to Grow Sweet Potatoes
Cultivate around the plants to prevent weeds, and to prevent side roots from developing. Weeds compete with plants for water, space and nutrients. Cultivate carefully so as not to bruise or cut the young tubers forming just below the soil. Once plants get started their growth will tend to smother out many weeds and grasses.
Provide sweet potato plants with about ¾ inches of water weekly when they are young, and water them more as the plants mature. Do not water during the 2 weeks before harvest.
Many gardeners prefer not to fertilize because they feel not fertilizing improves the flavor, while others feel that fertilizing increases yields. If you choose to fertilize, side dress with a balanced fertilizer about six weeks after planting. Do not use excessive nitrogen.
I recommend adding a cup of Organic Bone Meal to each ridge planted.
Monitor for pests and diseases. Check with your local Cooperative Extension Service for pest controls recommended for your area.
Harvesting and Preserving Tips
Harvest small roots, or “baby bakers” anytime as desired, or harvest full-sized roots in the fall. Simply examine an average hill and dig the potatoes when they approach the desired size. Dig any remaining roots before frost.
When digging sweet potatoes be careful not to bruise them. Use a shovel or large pronged fork. With a loose row, pull the soil away with your hands.
After digging up your sweet potatoes, cure them in a warm, well ventilated location out of the sun for 8-10 days. This will help heal cuts and bruises and toughen the skin for winter storage.
Store sweet potatoes at 55°F at high humidity. Sweet potatoes can store for several months after being properly cured.
Eat sweet potatoes baked, mashed, candied, caramelized, deep-fried, stuffed or boiled. My favorite dish is sweet potato casserole at Thanksgiving.