How to Grow Sweet Potatoes

Sweet potatoes thrive in warm, hot zones with long growing seasons. Sweet potato slips need 85 to 120 days to mature into sizable tubers.

To get started growing sweet potatoes, select a sunny site in your garden, with at least 8 hours of sunlight each day. You can grow sweet potatoes either in-ground or in raised garden beds. In both spaces, you’ll need loamy, well-draining garden soil.

If you’re a small space gardener, keep in mind that you can grow sweet potatoes in containers like buckets and grow bags (see more info below).

Sweet potatoes are planted from slips. Slips are small plants with stems, a few leaves and roots. Beauregard is the best known sweet potato variety. It takes 105 to 110 days to mature. Beauregard sweet potatoes are known for dark orange flesh and light purple skin.

When shopping in the Garden Center, you may find two kinds of sweet potatoes. They're both from the family ipomoea. Ornamental sweet potatoes are grown for their chartreuse vines. They're outstanding in container gardens, and while these plants will form tubers, they are not bred for taste. Save sweet potato vines for your annual containers. Look in the garden vegetable section for sweet potato slips to grow for edible sweet potato tubers.

Root crops like sweet potatoes grow well in raised garden beds, especially if your garden's soil is heavy clay. Sweet potatoes, like all root vegetables, need aerated soil for good root development. If you’re planting sweet potatoes in the ground, amend the soil with organic compost before planting.

Sweet potatoes like acidic soil, with a pH in the range of 5.8 to 6.2 (Neutral is 7.0). Perform a soil test to determine your soil’s pH and get recommendations for amending the soil. Soil tests are available in the Garden Center, online and also from your local Extension office. If your soil’s pH is neutral or alkaline, amend it with peat moss or organic compost.

Sweet potatoes appreciate a warm bed before planting. You can plant sweet potato slips when the soil temperature reaches 65 degrees Fahrenheit. In southern climates, this is typical for late spring days. In the north, where the growing season is shorter, try warming the soil with a black plastic cover several weeks before planting.

Tip: Measure soil temperature with a soil thermometer, found in the Garden Center and online.

To plant sweet potatoes in your garden, you’ll need:

• Spading fork

• Watering can

• Mulch

• Organic fertilizer

• Garden hose

• Gardening gloves

• Garden shovel or trowel

• Sweet potato slips or plants

When you’re ready to plant in the prepared garden bed, dig holes 18 inches apart and rows 3 feet apart. Leave room for the sweet potato vines to sprawl throughout your garden.

Before planting each slip, pour water into each hole. Place the slip in the hole and pull the soil around it. You can apply organic mulch around the plants to suppress weeds and retain moisture. When you're finished, use the garden hose or a watering can to saturate the bed with water.

If you’re growing sweet potatoes in a container like a grow bag, bucket or other planter, keep in mind that the roots of your sweet potatoes need a lot of room to grow. Experts advise planting only one sweet potato slip per 5-gallon bucket.

Tip: When planting sweet potatoes in containers, be sure the planter has plenty of drainage holes in the bottom.

You’ll have the best chance of weeding your sweet potato bed about two weeks after you plant. The best practice is to gently hand-pull weeds. Garden tools like cultivators and hoes may disturb the new roots of tender sweet potato slips.

Use a continuous-release organic fertilizer or a water-soluble plant food on growing sweet potatoes. You’ll want to water about once a week for the first couple of months. Gardens need about an inch of water each week, from either rain or irrigation.

Deer love to nibble on sweet potato leaves. Deer-proofing strategies like fences, deer spray and electronic repellents may all work. Be sure to check that any chemical repellents you use are safe to use around edibles.

Barriers like floating row covers may prevent deer and other pests from damaging your plants, as well.

Pests like sweet potato weevils, wireworms and nematodes can attack the growing tubers. If you suspect these pests are in your garden soil, contact your local Extension office for advice on organic solutions.

Sweet potato tubers mature in 85 to 120 days (about 4 months). The foliage turns yellow, signaling that the tuber has stopped growing. When you’re ready to harvest, locate the crown of a plant and use a digging fork to gently loosen the soil in a circle around the plant.

You may find it helpful to shear off the vines before digging. Hand-pull the loosened tubers and soil out of the ground.

Sweet potatoes need a period of about 10 days in a warm, dry place to cure. This step helps develop the sugars in the tubers.

After you dig up the sweet potatoes, wash them and lay them in a single layer in a cool, dry place, like a table that’s shaded from the sun and rain. After 10 days, you can use the sweet potatoes.

Store sweet potatoes indoors in a cool, dry place. Do not store sweet potatoes in the refrigerator or in temperatures below 50 degrees Fahrenheit.