Harvesting, storing fall garden produce
By David Lott
UNL Horticulture Extension Educator
Cooler weather is approaching after a hot and unusually dry summer. While the change in temperature can be a welcome sign, cooler weather is also a sign up upcoming frost. Now is time to start thinking about when to harvest and how to store garden produce so it can be enjoyed later in the year.
Cold tolerance of produce varies with the crop. Some will need to be harvested before a frost, while others can withstand colder temperatures. Here are some simple guidelines to follow.
Warm weather loving crops that do not tolerate frost and low temperatures very well include tomatoes, peppers, sweet potatoes, okra, eggplant, cucumbers, and summer squash. Watermelon, cantaloupe, pumpkin, corn, peppers and eggplant are also very sensitive at these cool temperatures, often resulting in plant damage or death. Plants in the garden from this group can be damaged or killed at temperatures around 32 degrees Fahrenheit. Harvest produce from these plants before a killing freeze occurs.
Crops that withstand a light frost between 30 and 32 degrees Fahrenheit include beets, mustard, Chinese cabbage, radishes, collards, spinach, potatoes, Swiss chard, Bibb lettuce, green onions and leaf lettuce.
Crops that can withstand several freezes, but are not killed when temperatures drop near 20 degrees Fahrenheit include cabbage, carrots, broccoli, cauliflower, rutabagas, Brussels sprouts, and kale.
How can this produce harvested? Take the time and effort to gently harvest and move produce to avoid bruises and cracks. This damage will greatly reduce the shelf life of produce. Gently brush off soil or debris on produce after it is harvested.
Storage and shelf life of produce varies by the crop that is being stored. Providing a storage place with high humidity, low light, and the preferred temperature will help these crops last longer in storage. Here are some storage suggestions for some of the more popular produce crops that will be harvested this fall.
Tomatoes are a popular garden crop that can be seriously damaged by a frost. Harvest as the temperature cools. Harvest the last undamaged red-ripe and unripe tomatoes right before a killing frost. Remove the stems and rinse tomatoes with cracks or splits in a solution of 1 1/2 teaspoon of chlorine bleach mixed in one gallon of clean, lukewarm water. Dry the rinsed tomatoes completely with a soft cloth. These steps will help reduce the chance of decay in storage. Pack tomatoes in one or two layers in a shallow box. Store in a location where the temperature is between 46 and 50 degrees Fahrenheit and 90 percent humidity. Use the ripe tomatoes first. Bring unripe tomatoes into a place with a temperature of 70 degrees Fahrenheit to aid ripening.
Sweet peppers are another crop that can be harvested and stored before cool temperatures arrive. Once the daytime temperature stays below 45 degrees Fahrenheit on a consistent basis, start picking and storing firm sweet peppers that are free from damage. Rinse these peppers in a solution of 1 1/2 teaspoon of chlorine bleach mixed in one gallon of clean, lukewarm water. Thoroughly dry the peppers with a soft cloth before storing. Store peppers in boxes lined with plastic or plastic bags with holes punched in them to allow air circulation. Store in a location at a relative humidity of 90 percent, and a temperature range of 45 to 50 degrees Fahrenheit. Some of the sweet peppers may turn red while in storage. Many of the hot peppers store better after they are dried. For more information about drying peppers, refer to "Drying Foods at Home" by Purdue University Extension. This publication be accessed and viewed at http://www.extension.purdue.edu/extmedia/CFS/CFS-146-W.pdf for future reference.
Pumpkins should be harvested when the rind is mature before frost. Leave some of the stem to protect against bacteria and other organisms from entering the stem end of the pumpkin. Pumpkins should not be cured or stored with apples. Cure pumpkins in a single layer in room with ample air circulation relative humidity of 80 to 85 percent, and a temperature between 80 and 85 degrees Fahrenheit for 10 days to extent storage life. After this curing process, pumpkins can be stored in a single layer at a relative humidity of 50 to 75 percent, at a temperature range of 50 to 55 degrees Fahrenheit.
Potatoes are easily stored for a few months after harvest. Carefully remove all soil and debris before storing. Do not wash before storing. They need to be stored in an area that is high in humidity at 65 to 70 degrees Fahrenheit for one to two weeks for any wounds to heal over. After this period is complete, they can be stored in a dark room with moderate humidity at 40 to 45 degrees Fahrenheit.
Onions should be cured by home gardeners by laying onions in a single layer on mesh screen in a shady spot for one to two weeks, or until the tops of the onions have dried up. After this curing period, onions can be stored in shallow boxes or mesh bags to help facilitate air circulation. Cool temperatures down to 32 degrees Fahrenheit will help onions last longer in storage.
For more information on storing specific produce crops, please refer to "Storing Fresh Fruits and Vegetables" by the University of Nebraska-Lincoln Extension. This publication can be found at http://www.ianrpubs.unl.edu/pages/publicationD.jsp?publicationId=529.