Sweet potatoes, any way you serve them, are yummy and very nutritious. They are one thing that you can plant in the garden from April until the first of July, so you still have time to get them in the ground. I received some slips of ‘Bradshaw’ sweet potato recently and am looking forward to growing them in the garden at the Clemson Extension office. David Bradshaw was one of the most beloved professors in the Horticulture Department, and he was very involved with organic and heirloom plants at the South Carolina Botanical Garden. The sweet potato was developed from the Mahon Yam (which is really a sweet potato) by Dr. Bradshaw and given to one of my classmates who has grown it for many years, saving a few each year to grow out the slips.
Soil preparation, in my case, means weeding out the cool season greens that had played out and were going to seed. By adding some compost and organic fertilizer, I was confident that the nutritional needs of the plant would be satisfied. Using a low nitrogen fertilizer promotes the tubers’ growth without excess foliage. This variety is supposed to do well without a lot of water and loves the heat. The garden receives 8-10 hours of sun and is very close to a water source. I have laid in drip irrigation and plan to give the plants a good soaking at least once a week. For weed control, I will mulch with coastal bermuda hay. Sweet potatoes have a long growing season, approximately120 days to maturity. I will need to dig them in the late fall before frost, but I may explore under the mulch in September.
Sweet potatoes are often called yams, but yams are from the plant Dioscorea batatas in the lily family and grow mainly in tropical countries: parts of Africa, Asia, and the Caribbean. Yams are a staple African food and found in markets that cater to several different cuisines. The skin of yams is dark and resembles bark. The ends of the tubers are rounded or blunt. The starchy flesh is a good source of potassium and fiber. Sweet potatoes originated in South and Central America, and the skin is smooth brown, yellow, or orange. The flesh can be dark orange, yellow, and even purple, and both ends are pointy. The plant genus is Ipomea, and it is a tropical member of the Morning Glory family. They can be eaten in so many ways, baked, fried, boiled, mashed, grilled, in casseroles, and pies. They have a very long shelf life because of curing, a process that turns some of the starches to sugar and gives the skin a chance to dry out and heal over any wounds.
I will also experiment with harvesting and eating the leaves. This is commonly done with regular sweet potatoes. The leaves can be enjoyed either streamed, stir-fried, or fresh in a salad.
For more information and recipes, see HGIC 1322, Sweet Potatoes, and HGIC 3538, Sweet Potato Basics.