Onions are a strong-flavored vegetable and can be used in a variety of ways. Deep-fried onion rings and French onion soup are favorites. Popular uses for onions include seasoning in salads, soups, casseroles, main dishes, sauces, and relishes. Green onions are available in the spring while other varieties peak in Ohio from August 1 to October 15.
For information on onion varieties in Ohio, contact your county educator in agriculture and natural resources at Ohio State University Extension, or a master gardener volunteer. 
Selection
- Green onions - Select fresh, dry, crisp onions free of decay.
- Dry onions (red, white, and yellow) - Select bright, clean, hard, well-shaped onions with dry skins that crackle. Do not select onions with a thick, woody, tough or open condition of the neck or those with the presence of a stem—these are indicators of seed stem development. Moisture at the neck is an indication of decay. Onions should be free from green sunburn spots and other blemishes.
Yield
Due to many variables such as moisture content, size, and variety, it is difficult to give specific recommendations. The recommendation below are approximations.
- 1¾ pounds onions = 3 cups
Nutrition
The Dietary Guidelines for Americans recommends 2½ cups of a variety of vegetables each day as part of a healthy diet. Although usually consumed in small quantities because of their zesty flavor profile, onions can help meet this nutritional requirement:.
- A cup of onions contains only 30 calories.
- They are a good source of vitamin C, potassium, and fiber.
- Onions are one of the highest sources of quercetin, a phytonutrient.
Storage
- Green onions - Keep cold and moist in the refrigerator. Store in plastic bags. Refrigerated shelf-life for green onions is often at least five days before spoilage.
- Dry onions - Store onions in a cool, dry, dark place to prevent sprouting and decay. Be careful not to bruise them. Be sure to cure onions to harden and dry the outer scales before you store them. Cured onions can be stored in loosely woven or open-mesh containers for several months.
- Do not wash before storing.
- Wash onions just before serving. Remove outer layers that may hold soil. Wash onions thoroughly in cold water to remove dirt. Do not use soap, detergent, or bleach because these liquids absorb into the vegetable.
Serving
- Onions can be added to many dishes, both fresh and cooked.
- Caramelize onions by heating over low heat with oil to achieve the desired color and consistency.
- Onions may also be served creamed, scalloped, au gratin, fried, baked, stuffed, sliced, or deep-fried.
- The following herbs may be paired with cooking onions: caraway seed, mustard seed, nutmeg, oregano, sage, thyme, chili powder, marjoram, dry mustard, rosemary, cloves, and dill. Use ¼ to ½ teaspoon dried herbs for each 2 cups of vegetable. Chop fine to release flavoring oils and then add at the beginning of cooking.
Roasted Root Vegetables
Roasting root vegetables adds a delightful, sweet taste. Cut vegetables into chunks that are similar in size so they will finish roasting at the same time.
Time: Approximately 1 hour and 15 minutes
Yield: 6 servings
Ingredients
- 4 medium-sized root vegetables (choose a variety from potatoes, rutabagas, turnips, parsnips, beets, sweet potatoes, etc.)
- 2 chopped carrots
- 1 medium chopped onion
- ¼ cup vegetable oil*
- Season with your favorite spices**
Cooking Instructions
- Preheat oven to 350 F.
- Cut vegetables into large chunks.
- Place in a medium bowl and pour oil over top. Add seasonings and mix well.
- Spread in an even layer on a baking sheet.
- Bake for 1 hour or until tender. Check a few vegetables to see if they are tender. Start checking the vegetables for tenderness at about 45 minutes.
*Depending on the size of your vegetables, you may be able to use slightly less oil. You might add one tablespoon of oil at a time until the vegetables are coated.
**Seasoning ideas: Try a mixture of ¼ teaspoon of dried thyme, ¼ teaspoon dried rosemary, and ? teaspoon black pepper on the vegetables. Another possibility would be to substitute ½ teaspoon Italian seasoning for the thyme and rosemary.
For information on preserving onions, go to ohioline.osu.edu, or contact your local Ohio State University Extension office for the following fact sheets:
- Canning Basics, HYG-5338
- Basics for Canning Vegetables, HYG-5344
- Freezing Vegetables, HYG-5333
- Drying Fruits and Vegetables, HYG-5347
References
National Center for Home Food Preservation. n.d. University of Georgia, College of Family and Consumer Sciences (website). Accessed July 29, 2021.
nchfp.uga.edu
University of Nebraska-Lincoln. n.d. “Roasted Root Vegetables.” Recipe Central. Accessed July 29, 2021.
food.unl.edu/fnh/roasted-root-vegetables
U.S. Department of Agriculture, Agricultural Research Service. FoodData Central, 2020.
fdc.nal.usda.gov
Revised 2021: Abigail Snyder, Food Safety Field Specialist, Family and Consumer Sciences, Ohio State University Extension
Original reviewer: Lydia Medeiros, PhD, RD, Specialist, Ohio State University Extension
Original author: Barbara A. Brahm, Educator, Family and Consumer Sciences, Ohio State University Extension