Sweet potatoes have certainly grown more popular than ever. Not only are they an incredible source of vitamins and essential fiber, but they also have a lower sugar index than traditional white potatoes, making them quite the healthy choice.
Even though they are extremely frost-sensitive, they can be grown successfully from slips in cooler climates, provided a few key conditions are met.
Sweet potatoes are not grown from seed. They’re grown from slips, which are sprouts grown from existing sweet potatoes.
They can also be grown in raised beds or large containers. Plant in an area with full sun and afternoon shade.
Plant sweet potatoes 2-3 weeks after the last spring frost, when the soil temperature is at least 65℉.
If it is still too soon to plant outdoors, stand the slips in potting mix or sand and keep moist until planting time (3 to 4 weeks after the last frost).
Harden off the slips (before planting outdoors) for 1 to 2 weeks by exposing them to filtered sunlight outdoors.
Sweet potatoes should not be planted outdoors until the temperature of the soil has warmed to 65 degrees Fahrenheit. They need soil growing temperatures between 65 to 85 degrees Fahrenheit and an air growing temperature of 65 to 95 degrees Fahrenheit. Choose short-season varieties if you live in the northern part of the country.
Sweet potatoes aren’t too picky, but they do prefer soil on the sandier side. They need plenty of air space in the soil for roots to reach down. If your soil is clay, rocky, or compacted, consider growing in raised beds. To give them a head start, sweet potatoes are often planted in raised rows, about 8 inches high. This helps the soil warm faster and keeps them well-drained. If you are gardening in a cooler climate, spreading black plastic on the soil will also help it warm faster
Add compost as well as perlite and/or coconut coir to the growing area to build fertile, loamy soil down to 8 to 10 inches. Avoid adding animal manure, including pelleted chicken manure; it can result in spindly and/or stained roots. Also avoid heavy nitrogen fertilizers, which produce lush leaf growth at the expense of the edible roots!
Once established, sweet potatoes will tolerate growing in dry soil. It’s best to keep it evenly moist with 1 inch of water given once a week. Don’t water your sweet potatoes during the final three to four weeks before harvest to prevent the mature tubers from splitting. Keep the plants moist, especially during dry spells.
Create raised mounds 6 to 8 inches tall and about 12 inches wide.
Plan 3 feet between mounds and about 12-18 inches apart in a row so that there is enough space for vines to run.
Plant the slips on a warm, overcast day, when the soil temperature has reached 65°F.
Break off the lower leaves, leaving only the top ones.
Set the slips deep enough to cover the roots and the stem up to the leaves. Sweet potatoes will form on the nodes.
Water with a high-phosphorus liquid fertilizer, then water generously for 7 to 10 days to make sure that the plants root well.
Slips may look droopy. Transplanting can be quite a shock! With time and warming temperatures, however, the transplants will perk up. A layer of row cover can act as a protective, warming blanket.
Side-dress the sweet potato plants 3 to 4 weeks after transplanting with 5-10-10 fertilizer. If you have sandy soil, use more.
Weed the sweet potato beds regularly starting 2 weeks after planting.
Avoid deep digging with a hoe or other tool that disturbs the delicate feeder roots.
Water regularly, especially during mid-summer. Deep watering in hot, dry periods will help to increase yields.
Do not prune sweet potato vines; they should be vigorous.
Late in the season, reduce watering to avoid cracking of the sweet’s skin—a problem in storage.
You can start digging up the roots as soon as they are big enough for a meal.
Harvest when the leaves and ends of the vines have started turning yellow or about 100 days from planting.
Loosen the soil around each plant (18 inches around, 4 to 6 inches deep) to avoid injuring the roots. Cutaway some of the vines.
Pull up the plant’s primary crown and dig up the roots by hand. Handle the sweet potatoes carefully, as they bruise easily.
Shake off any excess dirt; do not wash the roots.
Complete harvesting by the first fall frost.
Beauregard (90 days) originally comes from Louisiana but grows well in the north. It has dark red roots, and dark orange flesh, and stores well.
Bunch Porto Rico (110 days) A great variety for folks with small gardens. Short compact vines produce roots with copper-colored skins and light red flesh. Popular for baking.
Centennial (100 days) is the leading variety in the U.S. It is carrot-colored and has a good storage life. It is also a good producer for northern growers.
Georgia Jet (90 days); Red skin covers moist, deep orange flesh. Extremely fast-growing type; good for the North.
Vardaman (110 days) is a bush type and good for small gardens; it has unique blue/purple foliage, golden skin, and reddish-orange flesh; stores well.
Did you know that before George Washington became a general and the first U.S. President, he was a sweet potato farmer? These tasty tuberous vegetables are native to the Americas and are a great addition to your diet. Here are just a few fun facts about the sweet potato and its myriad benefits.
“There is one thing that a sweet potato is not. And that is a potato.” A sweet potato is a root. Potatoes are tubers. Since sweet potatoes are unrelated to white potatoes, the two should not be used as substitutes when cooking.
The orange-fleshed sweet potato is often called a yam. Again, the two are unrelated. True yams are starchy, underground tubers that likely originated in Africa. See the difference between yams and sweet potatoes.
Sweet potatoes as the #1 most nutritional vegetable, with more nutrients than even spinach or broccoli!
Benefits of the sweet potato include high levels of Vitamins A and C, iron, potassium, and dietary fiber.
Especially important is the high percentage of beta-carotene found in sweet potatoes. This is converted into Vitamin A, which has the ability to reduce the risk of certain cancers.
Sweet potatoes because they have almost no fat which also makes them great for those watching their weight. With their low carbohydrate content and high fiber content, sweet potatoes keep you full for longer and give you all the essential nutrients.
