Sweet potatoes experience a bit of a zenith during the Thanksgiving and Christmas holidays when their popularity soars. Sweet potato pies and casseroles are pretty popular, and lots of folks also enjoy what many people may call “candied yams.” In case you missed the memo, those are almost certainly sweet potatoes, not actually yams. (more info here: https://ncsweetpotatoes.com/sweet-potatoes-101/difference-between-yam-and-sweet-potato/ )
North Carolina is the country’s top producer of sweet potatoes growing nearly 60 percent of the country’s total crop. While sweet potatoes are generally harvested from late August to early November, with proper curing and storage they’re available year round.
“We’re able to sell year round without a reduction in quality of the product,” said Heather Barnes, a NCDA&CS marketing specialist.
Barnes knows a lot about sweet potatoes, not only because of her job but because her family grows sweet potatoes outside Wilson. She has a poster in her office that’s titled “A Year in the Life of a N.C. Sweet Potato,” and she’s co-written a children’s book about how sweet potatoes get from the farm to the plate. It’s a pretty good read for anyone interested in the basics of the process. Fortunately, there aren’t a lot of complicated steps, and generally the fewer steps from field to fork, the better.
Farmers don’t plant sweet potato seeds. Instead they get transplants (often called “slips”) from growers that specialize in sprouting transplants. Once they’re planted, the transplants grow roots and produce sweet potatoes underground as vines grow above ground. Sweet potatoes are ready to be harvested anywhere from 90 to 120 days after the transplants go in the ground.
A special plow goes through the field and flips the soil. With the dirt broken up, some sweet potatoes pop to the surface while others remain mixed in with the loosened dirt. Workers walk through the fields with buckets to pick up the sweet potatoes.
“Literally, a person picks up every sweet potato out of the field,” Barnes explained.
Workers sort the sweet potatoes by size as they gather them, and what happens next depends on where the sweet potatoes are headed. Most go into wooden boxes or bins and are taken to a storage facility for curing. The boxes are stacked in the building and kept for about four to seven days at a temperature between 90 and 95 degrees Fahrenheit and around 80 to 90 percent humidity. The curing sweetens the potatoes by converting some of the starch to sugar. After curing, the storage room is cooled to between 50 and 60 degrees Fahrenheit and humidity stays at around 85 percent.
When cured, sweet potatoes can be stored for more than a year, and each year’s harvest is sold throughout the year. Many sweet potatoes are shipped to grocery stores, wholesalers, restaurant suppliers, etc. That’s where many people find the sweet potatoes that end up on their plates.
Some sweet potatoes are sent to processing facilities instead. Those sweet potatoes are used for a variety of products such as baby food and sweet potato fries.
“There are so many places to use sweet potatoes we really don’t have any waste anymore,” Barnes said.
Some farmers may cure sweet potatoes on their own, or not at all. That may be the case if they’re selling directly to customers (e.g., at a farmers market or roadside market). If you’re buying directly from a farmer, it’s okay to ask if the sweet potatoes are uncured or “green.”
Whether the potatoes are from the previous season/year or whether they’re “green” from this year, they’re perfectly edible either way. An uncured sweet potato just may need to be cooked at a lower temperature for longer to give it the sweetness of a cured sweet potato.
“We eat them year round, not just on holidays,” she said. “They’re so versatile.”
Barnes seeks out lots of ideas about how to cook sweet potatoes – often getting them from the North Carolina SweetPotato Commission. She said she often uses sweet potatoes as an ingredient in dishes when she’s cooking for her family.
“I’m getting ready to make sweet potato, chocolate chip mini muffins,” she said. “They’re so good!”
She even said there are recipes for cocktails that use sweet potatoes.