CORVALLIS, Ore. — Want your homegrown potatoes to stay fresh longer? Follow best practices for harvesting and storing to ensure quality and reduce waste.
To prepare potatoes for storage, reduce watering in mid-August and allow vines to die back completely before harvesting.
Begin by checking for harvest maturity. Dig up a potato and rub the skin. If the skin rubs off easily, wait another week before harvesting, said Heidi Noordijk, Extension Small Farms coordinator with the Oregon State University Extension Service.
To prepare potatoes for storage, reduce watering in mid-August and allow vines to die back completely before harvesting.
Clean potatoes before storage. If your soil is coarse and sandy, gently brush off the soil. In fine, sticky clay soil, you may need to rinse the tubers. In either case, ensure potatoes are completely dry before storing. Minimize exposure to light during the cleaning process.
Cure newly harvested and cleaned potatoes in a dark, well-ventilated space with moderate temperatures and high humidity for 7 to 10 days. Curing helps extend storage life. After curing, gradually lower the storage temperature to 40–46°F for table use. Because tubers are about 80% water, high humidity is essential to prevent shriveling.
Storage conditions
Store potatoes in perforated plastic bags or well-ventilated containers to maintain humidity. Suitable storage areas include refrigerators set to 40–46°F, insulated garages or cool basements.
Avoid temperatures below 38°F, which can cause sugar buildup and sweetening. Tubers stored at low temperatures may produce darker, oilier fried products. On the other hand, high temperatures can cause decay, sprouting and shriveling.
Sorting and managing spoilage
Before long-term storage, sort and discard any injured or diseased tubers. Use potatoes with cuts, bad spots or signs of disease within the first month, as damaged tubers don’t store well and may spread decay.
Keep the storage area dark. Exposure to light can cause greening, making tubers unfit for consumption. The green color comes from chlorophyll, which is harmless, but often signals the presence of solanine — a toxic compound. Discard any potatoes with excessive greening.
Choose varieties that store well
Some potato varieties naturally store better than others. Red potatoes and thin-skinned types generally have shorter storage life compared to thick-skinned varieties like russets. Late-maturing varieties typically store better than early types.
With proper storage, mature, late-season potatoes can remain in good condition for seven to eight months. At temperatures above 46°F, expect storage life to drop to two to three months, with some risk of sprouting and shriveling.
“Planting sprouted or shriveled tubers the following spring is not recommended due to potential disease issues, especially viruses,” Noordijk said. “Whenever possible, plant only certified, healthy seed potatoes.”
Previously titled Tips on keeping harvested potatoes fresh
