“I don’t have any good-size sweet potatoes, maybe I planted too late, what should I do?” – Shirley Esau Whether the morning chill is a welcome arrival or not is a hotly contested debate in our home.
The chilly crowd finds it rejuvenating, mostly die-hard carrot lovers, looking well-forward to the first frost and the corresponding jump in sweetness. Unfortunately for our other camp, the “warm-blanket brigade,” and our dear friend the sweet potato, the morning chill is firmly here, and they all need care to make it well through winter.
C onditions Regardless of USDA Zone, the basic requirements to grow sweet potatoes are 120 frost-free days in the season, ideally a free-draining and sandy loam raised bed, 24 inches wide, at least 8 inches high, and having 24-inch paths between rows, as well as the space to let vines go where they may.
It is no secret that these tough plants are a reliable crop in Putnam County (Zone 8a). The varieties “Covington” and “Georgia Jet” live up to their reputations as excellent varieties for the Eatonton gritty clay backyard veg plot. Any improvement in drainage that isn’t too rich in nutrients will cause a noticeable increase in quality, especially regarding nematode and rot damage when the rain gets heavy.
In Putnam County you can plant sweet potato slips as soon as overnight temperatures are reliably higher than 60F.
Harvest now, when you see the vines starting to die back a little, but well before the first frost. The die-back is the sign that the tubers are consuming and storing the last bit of energy of the vine.
Once dug, you don’t want to leave sweet potatoes in the sun. Let the dirt dry and then rub it off gently with your hands or a dry terry cloth towel. My garden shed is raised about 16 inches off the ground, and so long as we are still in the high 70s to low 80s, I put mine in big plastic IFCO produce totes under the shed to cure in the shade with good ventilation.
For an easier approach, try curing them in a large brown paper grocery store bag in the bottom of a warm closet or on a shaded and dry porch, opening the bag every few days to freshen the air. After three weeks of curing, the starches in the potato will have converted into sugar during the curing process.
Looking forward
If your vines failed to produce tubers of adequate size, you planted too late. I overwinter these underdeveloped tubers, as well as any rooted sections of vine that I pull up during harvesting in a vermiculite filled cardboard box in a cold-frame. In Zones 9 and above, you can replant these small sections in containers, wait for the vine to die back, and mulch heavily to protect from frost.
Until next time, Your Eatonton Gardenerd This week’s jobs: Weed – Plant shrubs and trees - Gather garden waste.
Fellow Gardenerds! Send questions, concerns, and tips to: garden. nerd.31024@gmail.com