Sweet Potatoes Make Gardening Easy

Sweet potatoes not only serve the traditional role of a vegetable, but are also used in desserts such as cakes, pies, and puddings. The attractive sprawling vines may be used for their ornamental value in patio planters or as indoor houseplants. Throughout the United States the terms sweet potato and yam are used interchangeably. Yam sometimes indicates a moist-fleshed type. In many parts of the world, however, the term yam refers to another vining plant with tuberous roots which belongs to the plant Dioscorea. The vine appearance of the true yarn is similar to an ornamental vine known as cinnamon vine, while the sweet potato produces a vine similar in appearance to ornamental morning glories.

Sweet potatoes like warm soil and hot weather. There is little gained by planting them while weather is cool. Rooted plants grown from shoots taken off the tuberous roots are planted into the garden. Black plastic mulches are particularly suited to sweet potato growth. The black plastic, helps warm the soil quickly and also holds in moisture, making plants develop more quickly. Sweet potatoes may be grown in many types of soils, but are best adapted to sandy loams. In sandy soils, bright, clean, straight roots are produced. In heavier soils roots may be misshapen and rough. Sweet potatoes require good drainage.

Drainage is not normally a problem in sandy soils, but in heavier soils rows may be raised on ridges to insure good drainage. This also allows easier digging at harvest time. Although sweet potatoes need excellent drainage, they also need adequate moisture. In mid-to-late summer while they are developing their storage roots, they should receive about 1 ½ inches of water at least every 10 days. If this is not received from normal rainfall, it should be supplied by irrigation. Too much water, however, may result in decreased yield as well as poorer storage life.

Although there are many different varieties of sweet potatoes, the home gardener is usually limited to only one or two locally available. Centennial is a variety with wide adaptation and orange flesh. Jewel is a productive variety with good baking quality. Red Jewel is a mutant of Jewel which has a red skin. All Gold produces a high quality root with orange- flesh. Sweet potatoes have few problems in the home garden, and once plants are established, they spread rapidly. In the early stages they would be kept free of grass and weeds, but as the plants become more dense they compete well with weeds and require little additional attention.

There are few diseases of sweet potatoes, but black rot and soft rot may infect them in poorly drained areas, or after periods of excessively wet weather. Scurf is a fungus disease causing discoloration of the surface. While internal parts may be used, in storage the roots become dry and leathery. Make sure that seed stock is clean to prevent spread of this disease. Although few insect pests are a problem on home grown sweet potatoes some leaf eating pests may appear. These include the tortise beetle (goldbug) and flea beetle. Prompt treatment with an insecticide helps keep them under control when they appear.

The Vegetable Gardener's Bible, by Edward C. Smith.