How to Grow Sweet Potatoes: There is no denying the beauty of a sweet potato plant, whether it is placed on a trellis, in a garden or on a simple container. And the positives don’t stop there. When it comes to health benefits, sweet potatoes are worth considering as part of your diet. They are loaded with vitamins, minerals, fiber and phytonutrients that can strengthen your mind and body.
If you are curious to grow them yourself, keep in mind that they do better under the sun vegetable garden even if they can also thrive in other areas of your outdoor space. They can even act as a temporary ground cover or as a leakage houseplant. In a patio planter, a sweet potato vine will form magnificent foliage, the roots of which you can harvest in the fall.
This hot weather crop grows worldwide, from tropical regions to temperate climates. The flesh is classified as wet or dry. The wet and dark orange types (sometimes called yams) are more popular with home gardeners, especially the Centennial and Georgia Jet varieties.
Sweet potatoes are also remarkably nutritious and versatile; each fleshy root is rich in vitamins A and C, as well as many important minerals. Use them raw, boiled, or baked in soups, stews, desserts, breads, or stir-fries – and don’t forget to try homemade sweet potato fries! Here is everything you need to know to grow your own sweet potatoes.
How to plant sweet potatoes:
Sweet potatoes grow in poor soil, but deformed roots can develop in heavy clay or long and stringy in sandy soil. To create the perfect environment, create long, wide, and 10-inch high ridges spaced 3½ feet apart. (A 10-foot row will produce 8-10 pounds of potatoes.)
Work in a lot of compost, avoiding nitrogen-rich fertilizers that produce lush vines and stunted tubes. In the North, cover the raised rows with black plastic to keep the soil warm and promote strong growth.
It is best to plant root sprouts, called leaflets, available at nurseries and mail order suppliers. (Sweet potatoes bought in stores are often waxed to prevent germination). Save some roots from your crop for planting next year.
About six weeks before it’s time to plant sweet potatoes outdoors in your area, place the roots in a box of damp sand, sawdust or chopped leaves in a warm place (75 to 80 degrees). The shoots will germinate, and when they reach 6 to 9 inches long, cut them from the root. Remove and discard the bottom thumb of each slip, as this part sometimes harbors pathogens.
Sweet potatoes ripen in 90 to 170 days and are extremely sensitive to frost. Plant in full sun three to four weeks after the last frost when the soil has warmed up. Make holes 6 inches deep and 12 inches apart. Bury slides to the upper leaves, press gently but firmly on the soil and water well.
How to grow sweet potatoes:
If you are not using black plastic, mulch the vines two weeks after planting to smother weeds, retain moisture, and keep the soil loose for root development. Occasionally raise longer vines to prevent them from rooting at the joints, or they will put their energy into forming too many small tubers in each rooted area rather than ripening the main crop at the base of the plant . Otherwise, manipulate the plants as little as possible to avoid sores than spores of vulnerable diseases.
If the weather is dry, provide 1 inch of water per week up to two weeks before harvest, then let the soil dry out a bit. Do not overwater, or plants – which are more resistant to dry spells than rainy ones – may rot.
How to avoid parasites:
Gardeners in the South are more likely to experience pest problems than gardeners in the North.
Sweetpotato weevils – ¼-inch-long insects with dark blue heads and wings and red-orange bodies – puncture the stems and tubers to lay their eggs. Developing larvae tunnel and feed on fleshy roots, while adults usually attack vines and leaves. They also spread foot rot, which creates brown to black areas that grow on the stems near the ground and at the ends of the stems. As weevils multiply quickly and are difficult to eliminate, use certified disease resistant leaflets and rotate crops for four years. Destroy infected plants and their roots, or place them in sealed containers and dispose of them with household garbage.
Fungal diseases include black rot, which causes circular and dark depressions on the tubers. Discard the infected potatoes and carefully care for the intact roots of the same crop. Do not confuse this disease with less severe scurfers, which create small, round, dark spots on the surfaces of the tubers, but do not affect food quality.
Stem rot, or wilting, is a fungus that enters plants injured by insects, careless crops or the wind. Even if this disease does not kill the plants, the harvest will be poor. Minimize the risk of disease by planting only healthy tips; avoid black and stem rot by planting resistant cultivars. Reduce the incidence of dry rot, which mummifies stored potatoes, keeping the roots fleshy at 55 to 60 degrees.
Sweet potato harvest:
You can harvest as soon as the leaves start to turn yellow, but the longer a crop stays in the soil, the higher the yield and the higher the vitamin content. However, once the frost darkens the vines, the tubers can quickly rot.
Use a digging fork to dig the tubers on a sunny day when the soil is dry. Remember that tubers can grow a foot or more from the plant, and any nicks on their tender skin will encourage spoilage. Dry the tubers in the sun for several hours, then move them to a well-ventilated area and keep them at 85 to 90 degrees for 10 to 15 days. Once hardened, store at about 55 degrees, with a humidity of 75 to 80%. Sweet potatoes that are properly dried and stored will keep for several months.