Harvest Sweet Potatoes Before Cold Weather Arrives
Headquartered in Greene County
Tel: (417) 881-8909
SPRINGFIELD, Mo. – According to Patrick Byers, horticulture specialist with University of Missouri Extension, the best time to harvest sweet potatoes is before cold weather arrives.
“Sweet potatoes should be harvested by the time frost kills the vines or soon thereafter. Usually 130-170 days from planting are needed to give highest yields, although baby bakers or smaller roots can be harvested up to a month earlier,” said Byers.
In sweet potatoes, the roots continue to grow until frost kills the vines. However, an extremely hard frost can cause damage to roots near the surface. Chilling injury also results to roots when soil temperatures drop to 50 degrees Fahrenheit or lower, and this can result in internal decay in storage.
“Direct sunlight for over an hour can sunburn the roots, so dig only those that can be picked up immediately,” said Byers.
The greatest danger from delayed digging is in the effect wet soil has on the roots. Excessive moisture can prevent digging injuries from healing properly allowing decay of the roots.
“Keep in mind that disease control continues through harvesting and storing,” said Byers.
Sweet potatoes should be cured before storing to heal wounds and improve flavor. It is during the curing process that starch is converted to sugar. Cure sweet potatoes by holding them for about 10 days at 80-85 degrees and high relative humidity (85-90 percent).
Once the sweet potatoes are cured, move them to a dark location where a temperature of about 55-60 degrees can be maintained. Select only sound, whole roots that are free from disease and insect damage for long-term storage. Use cut pieces and damaged roots soon after digging.
For more information on sweet potatoes, or answers to your specific lawn and garden questions, contact Patrick Byers, horticulture specialist, University of Missouri Extension or the Greene County Master Gardener Hotline at (417) 881-8909. Information can also be found on the Greene County Extension website at http://extension.missouri.edu/greene.