Potatoes grown for fall and winter use should be carefully dug after the plants have died (turned brown) and the crop is fully mature. Most potato cultivars mature 90 to 120 days after planting. To check crop maturity, dig up one or two hills after the plants have died. If the skin is thin and rubs off easily, the potatoes are not fully mature and will not store well. Allow the crop to mature in the soil for several more days before harvesting the rest of the potatoes.
When harvesting, avoid cutting or bruising the potatoes. Use damaged tubers as soon as possible. Don’t wash the potatoes. Gently rub off the soil with your hands. Washing may reduce the storage life of the potatoes.
Before placing the potatoes in storage, cure the tubers at a temperature of 45 to 60 degrees Fahrenheit and relative humidity of 85 to 95 percent for 2 weeks. Curing promotes healing of minor cuts and bruises and thickening of the skin. Once cured, sort through the potatoes and discard any soft or shriveled tubers. These potatoes may spoil in storage and cause other potatoes to spoil as well.
Potatoes should be stored in a dark location with a temperature of 38 to 40 degrees Fahrenheit and a relative humidity of 90 to 95 percent. Potatoes will sprout if storage temperatures are too warm. Potatoes develop a sugary, sweet taste when stored at temperatures below 38 degrees Fahrenheit. Do not allow potatoes to freeze. Possible storage locations in the home include an extra refrigerator (set a few degrees warmer than normal), an unheated spare room, cool basement, or insulated garage. To increase humidity levels, store potatoes in perforated plastic bags.
Do not store potatoes with apples or other fruits. Apples and many other fruits produce ethylene gas which promotes sprouting of potatoes.
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