The key to harvesting, curing and storing potatoes grown in your garden

Fresh, young potatoes are absolutely delicious. Fried, young potatoes with summer squash, onions, peppers, garlic, and a couple of eggs on top, with fresh salsa on it makes the breakfast of champions. On the other hand, potatoes stored through the winter need to be treated differently.

Harvest

Potatoes harvested before the vines die have a thin skin that is easily scuffed and bruised. The skin will toughen naturally after the vines die. It’s best to wait for a week or two after the vines die before harvesting. Otherwise, harvest and cure them before you put them in long-term storage. There is less damage when potatoes are harvested with a garden fork rather than a spade, and they should be dug before the ground freezes.

Any diseased or severely injured tubers should be discarded or used within a couple of weeks. Potatoes should not be exposed to the sun, as this will cause the skins to turn green and become bitter. They are also slightly toxic. The green ends can be peeled or cut off and prepared for consumption, but overly green potatoes should be discarded.

Cure

Potatoes shouldn’t be washed before storage, however, excess dirt should be removed. Curing will extend storage, if they didn’t cure in the ground, and should be done in a dark location at a cool room temperature (about 60-degrees) with about 95% humidity. In a home situation, it may be difficult to provide the ideal environment, so get it as close as you can. Make sure the tubers are dry and there is good air circulation. Cure the potatoes for 7 – 10 days. Inspect again for damage or disease before putting into storage.

Storage

Freshly harvested potatoes have a natural sprout inhibitor that keeps them from sprouting for 1 – 6 months, depending on the cultivar. Beyond that, the length of storability depends on temperature, humidity and the presence of ethylene (a natural plant hormone that promotes ripening). Thicker-skinned potatoes, such as russets, tend to store longer than thinner-skinned potatoes. Potatoes in storage should not be frozen.
Potatoes stored at temperatures below 42⁰F will convert starch to sugar more quickly, making the potatoes taste sweeter. When these potatoes are fried for chips or fries, they turn dark. The colder the storage, the faster the conversion. This is one reason refrigeration is not recommended. If they are baked or boiled, the color won’t be affected.

Potatoes stored in 42 to 55-degree temperatures will have a slower conversion to sugar and maintain a good color regardless of cooking method. However, when stored above 45⁰F they will begin to sprout much sooner. Ideal storage is 42 to 50-degrees at 95% humidity. Do the best you can.

Harvested potatoes are still living, respiring organisms. They need fresh air for prolonged storage so bags should “breathe” and containers should be accessed frequently. While potatoes are low ethylene-producers, they are sensitive to ethylene that is given off by other produce, such as apples and tomatoes. This hormone will shorten the shelf life of potatoes. The best environment for long-term potato storage is ventilated, dark, cool and humid. A spare refrigerator set at a warmer temperature will work well if the door is opened often to allow for air exchange. A cool, dark room in a basement or a root cellar can also be good.