AMES — Vegetable gardens may close down for the winter in Iowa, but gardeners can still enjoy the vegetables they have grown. Many vegetables keep for months in cold storage when provided the right conditions. Iowa State University Extension and Outreach horticulturists share information on vegetable storage. To have additional questions answered, contact Hortline at 515-294-3108 or at firstname.lastname@example.org.
My acorn squash are turning yellow. Why?
The problem may be improper storage. Acorn-type squashes should be stored at a temperature of 50 to 55 degrees Fahrenheit. Some acorn-type squashes will turn yellow when stored at temperatures above 55 F. High storage temperatures may also cause the flesh to become stringy.
Why are my potatoes
beginning to sprout?
Potatoes should be stored at a temperature of 40 F and relative humidity of 90 to 95 percent. Tubers often begin to sprout if storage temperatures are above 50 F. Also, don’t store potatoes with apples or other fruit. Fruit produce ethylene gas. Ethylene promotes sprouting of potatoes.
My sweet potatoes have
become dry and stringy. What caused this?
It’s likely the sweet potatoes were not cured and stored properly. After harvest, sweet potatoes should be cured for seven to 10 days at a temperature of 80 to 85 F and relative humidity of 85 to 90 percent. (Since it’s difficult for most home gardeners to provide these conditions, a good option is to place sweet potatoes in perforated plastic bags and set the bags in a warm (70 to 75 degrees) location in the home. Extend the curing time to 14 to 21 days.) Curing promotes healing of minor cuts and bruises, prolonging the storage life of sweet potatoes. Curing also improves the flavor of sweet potatoes as starches are converted to sugars during the curing process. After curing, store sweet potatoes at a temperature of 55 to 60 F and relative humidity of 85 to 90 percent. Sweet potatoes stored at temperatures above 60 F will shrivel and become dry and stringy. Sweet potatoes may develop an off-flavor and the flesh may become discolored when stored at temperatures below 55 F.
My onions don’t
store well. Why?
The storage life of onions is largely determined by the variety (cultivar) and storage conditions. When properly stored, excellent long-term keepers, such as “Copra,” “First Edition,” “Stuttgarter” and “Redwing,” can be successfully stored for several months. Poor keepers, such as “Walla Walla” and “Sweet Spanish,” can only be stored for a few weeks. Onions should be placed in mesh bags, crates or wire baskets and stored in a cool (32 to 40 degrees), dry location. If storage temperatures are too warm, onions may sprout. Rotting may be a problem in damp locations. Inspect stored onions on a regular basis in fall and winter. Discard any that are starting to rot.