Harvesting and Curing Sweet Potatoes

It's TimeTo Dig for Gold!

Content from  The National Gardening Association Editors

When to Harvest Sweet Potatoes?

Gardeners in North Carolina, the biggest sweet potato-producing state, time their plantings so the roots will mature by late September and early October. This gives them time to harvest before the first frost, so the potatoes are in storage as the weather turns cool.

Frost and cold weather can hurt sweet potatoes at harvesttime even though you might think they're insulated underground. When frost kills and blackens the vines aboveground, decay can start in on the dead vines and pass down to the roots. If your sweet potato plants suffer a frost one night, cut the vines off right above the soil first thing the next morning. This may let you leave the potatoes in the ground for a few more days without injury.

Try to dig the sweet potatoes on a dry, overcast day. Leaving them in direct sun for long can open pathways of infection that will damage the crop in storage. Dig gently around the hills, starting from a few feet away, so as not to slash any wandering roots with your shovel or fork.

Let the potatoes dry on the ground for a couple of hours. If you dig late in the day, don't leave the roots out overnight; you risk damage from cold weather and moisture. Don't wash the potatoes after the harvest, either. Sort any badly cut or bruised potatoes to eat first (they won't keep) and sort the rest according to size in boxes or baskets to cure before storage.

Let Them Cure

Curing can be done in 10 to 14 days by keeping sweet potatoes in a warm, dark place with some ventilation. The temperature should be 80 deg to 85 deg F with high humidity. Under these conditions, bruises and wounds will heal quickly, sealing out rot organisms.

After curing, put the containers of sweet potatoes in a dry, well-ventilated area at 55 deg to 60 deg F with a relative humidity of 75 percent to 80 percent. Under ideal conditions, you can keep a mature crop until the next early harvest. If you can't store your sweet potatoes under these conditions, you may want to cook and freeze your harvest.

Sweet potatoes bruise easily and can suffer quickly when handled in storage. It's best not to pick through them too often.