All good things must come to an end and I suspect that this gardening season does not have much time left. These cool mornings make me worry that one of them will include frost. Take a survey of your garden and plan the harvest accordingly. Different vegetables require different harvest times and storage methods also differ for the best results.
Let’s start with onions. Let them stay in the garden until the necks are tight and the scales (paper covering) are dry. Usually they are fine left in the garden into the fall but not if a frost is threatened. Avoid bruising them when picking. Lay them in the sun to dry down. Let them cure in a warm, dry place for two weeks before storing. Onions need to be stored cold and dry, 32-40 degrees with low humidity. Many houses do not have a cool enough space so a spare refrigerator is an alternative. Some varieties do not store well and need to be turned into onion soup.
Squash and pumpkins need to have a hard shell before harvesting but will not tolerate a hard frost. Try to leave some stem on. They can be cured in a warm, dry place for about 10 days before storing. Washing them with a weak bleach solution or an alcohol solution helps prevent molds and rot. They need to be stored in a cool, dry location, 50-60 degrees. Many basements fit this description. A variety we grow lasts until April this way. Summer squash, peppers and cucumbers do not store well, you can only expect a week or more if stored in a perforated bag, not in the refrigerator.
Tomatoes are late this year but will continue to ripen after picking. If you have a place to lay them out on newspapers they will ripen at room temperature. Again, try to leave some stem on. Do not store them in the refrigerator; they lose color and firmness and will not ripen further below 40 degrees. Washing with a weak bleach or alcohol solution and rinsing after picking will reduce the number that rot.
Some vegetables require cold and moist conditions for storage: 32-40 degrees with 95 percent humidity. Root cellars or a specially designed storage room are the only ways to achieve this with modern building methods. Beets, cabbage, kohlrabi, carrots, cauliflower, muskmelon, parsnips, rutabagas, turnips, and especially potatoes require this means of storage if not processed. Light should be excluded from potatoes to avoid greening. The green part forms a toxin called solanine that should be cut away. A feature you may want to consider is an underground root cellar. Houses built in the 50s with a fallout shelter are a real find.
Vegetables are not inert and continue to breathe after harvesting. Placing them in a closed container is not desirable: they need ventilation to prevent rot. There are alternatives for storage of vegetables like carrots and parsnips. Generally, we do not harvest all of our carrots until very late, sometimes after the top layer of earth has frozen. With parsnips, simply leave the ones you do not eat in the ground until the next spring; then dig as soon as you can. They actually improve in flavor this way. Rutabagas, turnips and parsnips can be waxed with paraffin to extend storage time as well.
Sometimes it is better to let someone else do the work and shop at the grocery store.
To learn more specifics about vegetable storage and harvest, click on “Yard and Garden at the University of Minnesota Extension website . Local Master Gardeners will respond to your questions via Voice Mail. Call 218-444-7916, leaving your name, number and question. Our Facebook page may also be of help to you: <https://www.facebook.com/Beltramicountymastergardeners/>.