Sweet Potatoes

Growing your own sweet potatoes is easier than you might think. Unlike regular potatoes, sweet potatoes are typically grown from young plants called slips. Give these warm-season plants plenty of sunshine, warm soil, and a little care early in the season, and they can reward you with a generous harvest by fall. Whether this is your first time growing sweet potatoes or you simply need a refresher, this guide will take you from receiving your plants all the way through planting, growing, harvesting, curing, and storage.

When Your Sweet Potato Plants Arrive

Sweet potato plants are surprisingly tough, but they may not look their best immediately after shipping. After spending several days inside a box, the leaves can be wilted, pale, or yellow. This does not necessarily mean the plants are unhealthy. Open your package as soon as possible and carefully unpack the plants.

If the slips appear dry or wilted, place them upright in a container with a small amount of clean water covering the lower portion of the stems or roots, keeping the leaves above the water. Place the container in a comfortable, bright location out of harsh direct sunlight while the plants recover. Change the water regularly and give the plants time to perk up before planting. If weather conditions aren’t suitable for planting immediately, the plants can be held temporarily while you wait for warmer conditions. The important thing is to keep them hydrated without submerging the foliage.

Wait for Warm Weather Before Planting

Sweet potatoes love heat and do not tolerate frost. Don’t rush them into a cold spring garden. Wait until the danger of frost has passed and the soil has thoroughly warmed. A soil temperature of approximately 65°F or warmer is a good target. Warm soil helps the plants establish quickly, while planting into cold, wet ground can slow growth and increase stress.

Choose a location that receives plenty of sunshine. Sweet potatoes perform best in full sun, preferably with at least 6 to 8 hours of direct sunlight each day.

Preparing the Garden

Sweet potatoes develop underground as enlarged storage roots, so soil structure makes a big difference. Loose, well-drained soil gives the roots room to expand and makes harvesting much easier. Sandy or sandy-loam soil is excellent, but sweet potatoes can also be grown successfully in heavier soils.

If your garden soil is hard or compacted, work in organic matter such as finished compost before planting. Raised rows or ridges can also improve drainage, warm the soil faster, and provide additional loose soil for developing roots. Avoid soil that stays soggy for extended periods.

How to Plant Sweet Potato Slips

Sweet potatoes need room for their vigorous vines and underground roots. A good general spacing is 10–14 inches between plants and about 3–4 feet between rows. Keep in mind that spacing can vary by variety. Some sweet potato varieties produce more vigorous vines or larger root systems and may perform better with additional room between plants. If your variety has specific spacing recommendations, follow those guidelines for the best results.

Make a hole deep enough to place several inches of the lower stem into the soil while leaving the leafy growing portion above ground, then firm the soil gently around each plant. Planting during the late afternoon, on an overcast day, or when temperatures are moderate can help reduce transplant stress. Water each plant thoroughly immediately after planting. Don’t worry if the plants look tired for the first few days; once their roots become established, new growth can appear surprisingly quickly.

Watering After Planting

Moisture is particularly important while sweet potato plants are becoming established. Keep the soil evenly moist after planting, especially during hot or dry weather. Once established, sweet potatoes become fairly tolerant of dry conditions, but prolonged drought can reduce growth and yield.

The goal is consistent moisture rather than constantly wet soil. Deep watering is generally better than frequent shallow watering because it encourages a stronger root system. Avoid keeping the garden saturated, as excessively wet soil can contribute to root problems and may cause developing sweet potatoes to split.

Controlling Weeds

The first several weeks after planting are the most important time for weed control. Pull or carefully cultivate weeds around the young plants while they’re getting established. Be careful when using a hoe because sweet potato roots develop beneath and around the plants.

As summer progresses, the vines spread across the soil and create a thick canopy. This naturally shades the ground and can dramatically reduce weed growth. Once the vines have filled in, sweet potatoes generally require relatively little maintenance.

Let Those Vines Grow

Sweet potato vines can travel several feet and may eventually cover a large portion of the garden—and that’s a good thing! Healthy vines capture sunlight that supplies energy to the developing roots underground. Unless there’s a specific reason to do so, avoid repeatedly cutting or trimming healthy vines during the growing season. If vines begin growing into paths or neighboring crops, gently redirect them instead.

How Long Do Sweet Potatoes Take to Grow?

Depending on the variety and growing conditions, sweet potatoes commonly require approximately 85–120 days from planting to harvest. For the most accurate estimate, refer to the days to maturity listed for the particular variety you purchased. Some varieties mature earlier than others, so the variety-specific information is a better guide than a general maturity range.

Warm temperatures and a long growing season generally produce the best results. Keep track of your planting date and the expected maturity period for your particular variety. As harvest time approaches, you can carefully move a little soil away from the base of a plant to check the size of the developing roots. If they’re still smaller than you’d like and frost isn’t a concern, give them more time.

When to Harvest Sweet Potatoes

Sweet potatoes should generally be harvested once they’ve reached a desirable size and before freezing weather arrives. The roots can continue enlarging in the ground, but leaving them too long may result in oversized or cracked roots. Choose a dry day for harvesting when possible.

Cutting back or moving the vines can make it easier to see where each plant is located. Carefully loosen the soil around the plant with a garden fork or spade, starting far enough away that you don’t accidentally damage the sweet potatoes. Lift the roots gently, as freshly harvested sweet potatoes have delicate skins that can be damaged easily. Small scrapes and cuts can shorten their storage life.

Do not wash freshly harvested sweet potatoes before curing or storing them. Gently remove loose soil and allow the remaining dirt to dry naturally.

Don’t Skip the Curing Process

Freshly dug sweet potatoes aren’t quite the same as the sweet potatoes you’ve enjoyed from storage. Curing allows minor wounds in the skin to heal and helps improve eating quality and storage life. Commercial curing conditions are typically very warm and humid—around 85°F with high humidity for approximately 5–10 days.

Home gardeners don’t always have a perfect curing room, and that’s okay. A warm, humid, protected location with good airflow can still provide useful curing conditions. Keep the potatoes protected from rain and avoid stacking them tightly together. Good airflow helps prevent moisture problems. After curing, move them to their long-term storage location.

How to Store Sweet Potatoes

Sweet potatoes prefer warmer storage conditions than regular potatoes. For long-term storage, aim for approximately 55–60°F in a dark location with good air circulation. Avoid refrigeration for long-term storage, as temperatures that are too cold can damage sweet potatoes and affect their quality.

Avoid washing the potatoes until you’re ready to prepare them for eating. Check your stored crop occasionally and remove any roots that begin showing signs of decay. Under good curing and storage conditions, sweet potatoes can remain usable for months.

A Few Keys to Sweet Potato Success

If you remember only a few things, remember these: wait for warm soil, give your plants plenty of sunshine, keep young plants watered, and provide loose, well-drained soil. Be patient and allow your variety enough time to mature, harvest before hard frost, handle freshly dug roots gently, and cure your sweet potatoes before storing them. Following these basics will go a long way toward producing a successful crop.

From Plant to Plate

One of the most satisfying parts of growing sweet potatoes is digging into the soil at the end of the season and discovering what’s been growing underneath those vines all summer. Start with healthy plants, wait for warm weather, give them plenty of sunshine, and let nature do the rest. With a little patience, those small sweet potato slips that arrive in the spring can turn into baskets of homegrown sweet potatoes by fall.

Happy growing!