~by Richard Jauron and Greg Wallace, Iowa State University Extension & Outreach
AMES – Fall is an excellent time to reap the benefits of home gardens. Produce harvested from personal plots can make for a bountiful feast. But storing and keeping produce including potatoes, onions and carrots fresh can become an issue. ISU Extension and Outreach horticulturists can help answer questions about storing produce. To have additional questions answered, contact the ISU Hortline at 515-294-3108 or hortline@iastate.edu.
What is the proper way to store potatoes?
After harvesting the potatoes, cure the tubers at a temperature of 50 to 60 degrees Fahrenheit and a relative humidity of 85 to 90 percent for two weeks. The curing period allows minor cuts and bruises to heal. Thickening of the skin also occurs during the curing process. Once cured, store potatoes at a temperature of 40 degrees Fahrenheit and relative humidity of 90 to 95 percent. Store the crop in a dark location as potatoes turn green when exposed to light. If storage temperatures are above 50 degrees Fahrenheit, the tubers may begin to sprout in two to three months. When stored below 40 degrees Fahrenheit, potatoes develop a sugary, sweet taste. Sugary potatoes can be restored to their natural flavor by placing them at room temperature for a few days prior to use. Do not store potatoes with apples or other fruit. Ripening fruit give off ethylene gas, which promotes sprouting of tubers.
What is the proper way to store onions?
After harvesting, dry or cure the onions in a warm, dry, well-ventilated location, such as a shed or garage. Spread out the onions in a single layer on a clean, dry surface. Cure the onions for two to three weeks until the onion tops and necks are thoroughly dry and the outer bulb scales begin to rustle.
After the onions are properly cured, cut off the tops about one inch above the bulbs. As the onions are topped, discard any that show signs of decay. Use the thick-necked bulbs as soon as possible as they don’t store well. An alternate preparation method is to leave the onion tops untrimmed and braid the dry foliage together. Place the cured onions in a mesh bag, old nylon stocking, wire basket or crate. It’s important that the storage container allow air to circulate through the onions. Store the onions in a cool, moderately dry location. Storage temperatures should be 32 to 40 degrees Fahrenheit. The relative humidity should be 65 to 70 percent. Possible storage locations include a basement, cellar, or garage. Hang the braided onions from a rafter or ceiling. If storing the onions in an unheated garage, move the onions to an alternate storage site before temperatures drop below 32 degrees Fahrenheit.
What is the proper way to store carrots?
After harvesting carrots, cut off the green tops one-half to one inch above the roots. Small amounts can be placed in perforated plastic bags and stored in the refrigerator. Large amounts can be buried in sand or sawdust and then stored in a cool, moist location. Storage temperatures should be 32 to 35 degrees Fahrenheit. The relative humidity should be 98 to 100 percent. Carrots are likely to sprout or decay if stored at temperatures of 40 degrees Fahrenheit or above. Carrots will wilt or shrivel if the relative humidity is less than 95 percent.
