Sweet potatoes are easy to grow. They are started from plants called “slips”. Several varieties are available for purchase at the garden center.
• Beauregard – 100 days to harvest, light purple skin, dark orange flesh, extremely high yielder
• Porto Rico – 100 days to harvest, yam family, orange, moist with a very sweet and delicious flavor, excellent for baking.
• Jewell – 100 days, orange flesh, good yield, excellent keeper.
• Vardaman – 110 days, golden skin, orange flesh, compact bush type, young foliage purple)
• Yellow Jersey – golden yellow skin, flesh color ranges from creamy white to bright yellow with an occasional pink variegation.
When to plant: Transplant sweet potato slips as soon as the soil warms up after last frost. Soil temperature can be accelerated by the use of black plastic laid over the soil.
Spacing and Depth: Soil should be loose and friable. Incorporate a low nitrogen fertilizer (5¬10¬10) at the rate of 2 cups per 50 square feet. Over fertilization causes very poor yields. Prepare a ridge 12¬15 inches high and 18 inches wide. Put a 2 inch furrow in the center of the ridge to help channel the water. Cover the ridge with black plastic, pinning it down on both sides. In two weeks the soil will be warm enough to plant.
Planting: Use a knife to cut a small slit in the plastic, repeating every 12 to 18 inches. Plant the potato plants in the slit, one per slit, and water in with about a cup of water per plant. Firm soil around the roots with your hands. While sweet potatoes can withstand dry weather, they should be watered during dry spells to reach a good size. The furrow will help channel water around the plants.
Harvesting: Small potatoes may be harvested after 90 days. For large sized potatoes, harvest around 120 days. Lift plastic and use a shovel or large pronged fork to carefully dig potatoes, being careful not to cut or bruise them. Be sure to complete harvest by the second week of October.
Storage: Place freshly dug potatoes in baskets or ventilated crates inside a warm building (about 85 degrees). Let the potatoes “cure” for 8 to 10 days. This helps to heal cuts and bruises that may have occurred during harvest and toughens the skin for winter storage. After the potatoes have dried out, place them in a permanent storage area where the temperature ranges from 50 to 60 degrees F. Use throughout the fall and winter as needed.