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The exact time when people began to use onions is unknown due to the onions fragile and highly decomposable tissue structure, but most agree that they have been farmed for 5,000 years or more. While the region where they were first discovered is unknown, they most likely originated from Asia, even though they grow on every continent. Historians do know that onions have been an important staple in many cultures for different reasons. It is believed that they were considered to be medicinal, and even magical in some cultures. They can be seen among the ancient Egyptian hieroglyphs, and in mummies. They were also important to the Roman, Greek, and European cultures for things such as food, dyes, and even toys. Onions eventually made their way across the sea on the Mayflower to America.



Before onions are planted, the fields are prepped and planted usually by machine. An onion planting machine is towed behind a tractor and seeds are funneled into an instrument that pushes the seed into the ground and covers it. Onions can either be planted using seed (most common), or transplanted into a field; this usually takes place in March to April.


Onions can be sensitive to various conditions such as the amount of sun, soil composition, and where they are being grown. Onions prefer a dry climate, with lots of sun. They also prefer soils that are high in organic matter, and have good drainage.


Onions are ready for harvest from August to October and are typically considered mature when about two thirds of their bulb is visible above ground. Once they are ready, the onions are lifted out of the ground by machine to loosen them from the soil and left to dry in the field for  7-10 days. After they are dried, the onions are harvested out of the field and trimmed with a machine. Finally, they are taken to a packaging plant where they are stored, aerated, and cooled before being distributed to stores and restaurants.


The US onion industry has a huge impact both domestically and internationally. The leading export destinations for the US are Mexico, Canada, Taiwan, and Japan. China and India are the the only two countries that produce more onions than the US.


There are many different standards onions have to meet before reaching the market place. According to the USDA, they have to be a certain size, grade, and maturity. Onions also have to have minimal defects and injuries in order to be seen as fit to sell. An inspection must be as accurate as possible, with samples taken from many different parts of a harvest. This insures that the quality is accurately represented for all parts of the crop.


Onions have to be stored in the right conditions in order to preserve their structure and to ensure a long shelf life. This is done by creating an environment where the onions have a large amount of air flow, and are kept in a cool place. It is also best to have the moisture contents low when storing onions, so that diseases and rot do not begin to form.


When being marketed, there are various labeling requirements. Each package much include information on: brand, variety, size, grade, color, count, weight, point of origin, and other pertinent information. There is a large fresh and storage market for onions, however, they can also be sold canned, dehydrated, and frozen. Onions can be sold individually, or in bulk.

Onions in Oregon

Eastern Oregon is the leading region in the country for onions, weighing in at about 1,724,700,000 pounds! Malheur, Umatilla, and Morrow counties produce the largest amount of onions. These counties are in the eastern regions of Oregon where the climate is warm and drier than other parts of the state, like the Willamette Valley. There are three common types of onions which are yellow, red, white, and sometimes other specialty onions.
Fresh bulbs of Yellow Onion
Yellow Onions

Yellow onions are the most common and are used in a variety of dishes. It has a tough skin, and thick juicy layers. This onion is enjoyed for its mild and slightly sweet flavor.

White Onion
White Onion

White onions have a very sharp, and potent flavor that can be favorable, but strong. These onions are thin, and are used both cooked, and raw.

Red onion
Red Onions

The red onion’s name refers to the dark red outer layer. Red onions are a popular choice for raw uses because of their mild flavor.

Other Onions

There are many varieties of onions that are not as common as those listed above, but you’ve probably encountered; pearl, heirloom, Egyptian Walking onions and many others fall into this category. These onions are favorable because of their varied flavor profile, and texture.


Onions have a very shallow fibrous root system. Unlike the tap root system, the onion’s roots spread out in different directions in order to access the most water and nutrients.


Onions have a bulb that grows below ground. This is the part of the plant that is most commonly eaten. The onion bulb has a rigid, papery outer layer, with a meaty inner layer.


The onion plant has many leaves that sprout directly from the top of the bulb. While the bulb grows underground, the onion’s leaves are visible above ground and are typically 6 to 18 inches tall depending on variety and environment.


The onion’s inflorescence is an umbel. When the onion is in the reproductive state it bolts, then produces its inflorescence above its leaves. Onions are harvested before they have bolted to insure optimum storage life.


Onions provide important nutrients and health-promoting phytochemicals. They are high in Vitamin C, a good source of dietary fiber, and folic acid. Onions also contain calcium, iron and potassium.

The USDA recommendations for daily vegetable consumption to be 2 1/2 cups per day and onions easily fit into this category. For more information about onion nutrition please visit the USDA website.



Yield: 4 servings

2 large sweet onions, cut into 1/2-inch-thick rings
2 1/2 cups all-purpose flour
Vegetable oil, for frying
1/2 cup cornstarch
2 teaspoons paprika
1 teaspoon cayenne
1 teaspoon finely grated lime zest
Kosher salt
1 1/2 cups milk
1 cup club soda
1 large egg

Watch how to make this recipe.

Preheat the oven to 200 degrees F. Set a cooling rack over a baking sheet.

Separate the onions into rings and put in a large bowl. Toss with 1/2 cup of the flour. Arrange the floured rings on the cooling rack; let stand for 15 minutes.

Fill a large, wide pot with 2 inches of vegetable oil and heat to 365 degrees F over medium-high heat. In a large bowl, whisk the remaining 2 cups flour with the cornstarch, paprika, cayenne, lime zest and 1 1/2 teaspoons kosher salt. Add the milk, club soda and egg and whisk to combine.

Working in 3 or 4 batches, add a small amount of the onions to the batter and then immediately place into the hot oil. Fry until crisp and golden, turning once, 2 to 3 minutes. Allow the oil to come back to temperature between batches.

Season the onion rings with salt. Serve immediately with your condiment of choice, or transfer to a cooling rack and keep warm in the oven until ready to eat.


Fun Facts

  1. There are less than 1,000 onion farmers in the US, but we rank third (behind China and India) in the world for onion production in tonnes.
  2. The world record for the largest onion was 18 lbs and is held by Peter Glazebrook.
  3. Onions make you cry because when cut open they release a sulfenic acid that irritates your eye glands, which then produce tears!
  4. The yellow onion is the most popular type of onion, consisting of 75% of all production.
  5. George Washington was known for eating an onion when he thought that he was getting sick. This could be because onions are high in vitamin C, and other beneficial components.
  6. Over 450 semi-truck loads of onions are eaten every single day.
  7. Onions are about 87% water.
  8. Onions were one of the foods that helped colonists survive the winter, since they are able to last about 6 months without spoiling, if stored properly.
  9. Americans eat about 20 pounds of onions per year per person.
  10. Most domesticated onion plants are annuals.

AITC Resources

Onion and Apple Sense Experiment

Kid Friendly Recipes: Porcupine Meatballs