VeggieHarvest

Where to Grow Sweet Potatoes

Wherever a minimum of four months of warm growing season can be satisfied.  They can be grown in colder climates, it is reccomended to use black plastic mulch to keep them warm.  The Sweet Potato is a warm-season crop, very tender to frost and light freezes. Other than extreme sensitivity to frost, sweet potatoes are easy to grow, mostly pest free, and once the transplants are anchored, they are drought hardy.  They are one of the few crops native to North America. 

In cooking recipies, the words yam and sweet potato are typically equivalent.  A yam is much larger, and comes from South America; they can be up to 8 feet long, and weigh up to 100 pounds.  A sweet potato is typically less than 12 inches long, and weighs about 1 pound. There are many who claim the sweet potato is the single most nutritious vegetable on the planet. The sweet poato grows like a vine, the tips of which are very attractive to any plant eating wildlife in your area.

Reccomended Varieties of Sweet Potatoes

Centennial; Porto Rico; Goldmar; Nemagold

Soil for Growing Sweet Potatoes

A light, sandy, not too fertile soil. This is the key, as too fertile ground will produce all top and no tubers, while too moist soil produces poor quality tubers. Rocks and other obstructions in the soil can hamper root development.

Planting Sweet Potatoes

When - As soon as the ground can be worked, early in the season.

How - Start slips with a sweet potato cut in half lengthwise. Lay the cut side down in a shallow pan of wetted peat moss or sand. Cover tightly with plastic wrap until sprouts appear, then unwrap. The slip is ready when it has 4-5 leaves and is 4-8 inches tall, and has roots. A second method is to place a whole potato in a jar, cover the bottom inch with water, and keep warm. When leaves form above the roots, twist sprouts off and plant in a deep flat, or if warm enough, outdoors. A third method is to take 6 inch cuttings from vine tips in fall just before frost. Place cuttings in water and, when rooted, plant in 6 inch pots set in a sough facing window for the duration of winter. By late winter you can take more cuttings from these.

Started shoots or slips are supplied by a few mail-order nurseries. Set out in rows 3-5 feet apart, with 12-15 inches between plants. To prepare the ground in April, full furrows with 1-2 inches of compost. Mound soil over compost to form at least 10" high ridges. This mini-raised bed optimizes both tuber size and quality, because tuber growth is easily hindered by obstructions in the soil. After all danger of frost has past, transplant slips into these ridges. Unlike potatoes, sweets are not true tubers and keep expanding as the vine grows.

HowSweet Potatoes Grow

The sweet potato is a sprawling morning glory that does not usually flower. The elongated tubers, high in starch content, are formed just below the ground surface.

Cultivating Sweet Potatoes

Once planted, the vines are usually on their own, as too much fertilizer produces all tops. Weeding is important until the vines take hold and spread.

Harvesting Sweet Potatoes

Dig the tubers when the foliage begins to turn yellow and mature. The skins are fragile and bruise easily. Store at just below room temperature, after curing for a few days.

Sweet Potato Pests

None of major importance.

Sweet Potato Diseases

None of major importance.