The versatility of growing conditions and the varieties to choose from has made onions one of the most prolific vegetables found growing worldwide. From prehistoric times to the present day, onions are a gastronomic staple that can be found in the diet of most cultures.
Home gardeners and commercial farmers both rely on the crop as a dietary and economical commodity.
A quick internet search can show the wide array of onions available and make a gardeners head spin. Check out “Different Types & Varieties of Onions” for more hard facts on that.
In the paragraphs below, you’ll see how deeply ingrained onions are in our society and why they’ve become a staple in countless gardens around the world.
What Countries Grow Onions?
Due to the prevalence of onions in the diet of countless cultures, the crop can be found growing in most countries.
Close to 9.2 million acres are dedicated to onion planting globally on an annual basis. China, India, and the United States are the top three onion-producing countries in the world with over 35 million tons of onions being produced cumulatively on an annual basis.
China is the largest producer with over 20.5 million metric tons being produced as of 2017.
With that being said, these countries do not stand alone in the reliance on the crop. Nearly 170 countries cultivate onions for domestic use annually, and only 8% of those harvested are for export.
Given the wide availability and reliance on onions as both a garden and industrial crop, one is hard-pressed to find a region where they are not considered a staple, as they have been for thousands of years.
What States Grow Onions?
California, Idaho, Eastern Oregon, and Washington are the top producing states in the US. There are less than 1,000 total onion farmers in the United States, but the country still ranks third in total production globally.
California tops the list of onion production, and as of 2015, they produced 31% of the nation’s onion crop. A large factor in their high yields comes from the fact that they are the only state that grow both a spring and summer harvest.
Only 16% of onions grown in California are spring harvested, but that accounts for 42% of the total onions harvested during the spring in the United States.
After California, Western Idaho and Eastern Oregon are the top producing onion regions in the country.
The area known as Treasure Valley in Idaho and Oregon’s Malheur County accounts for the production of over 25% of the total yellow onions in the country annually.
Specifically they grow mostly the yellow Spanish Sweet variety. In these areas onions are planted March through April and are then harvested from August through October.
The third most onion producing region in the country is Washington state. Onion farming is concentrated to the central and eastern sides of the state, both in the Columbia River Basin and north of the Tri-Cities area.
Onions in the Columbia Basin are grown once every three to four years on a farm while allowing other crops to rotate through in the interim.
The city of Walla Walla, WA located southeast of the Tri-Cities, and near the Idaho and Oregon borders is known for a specialty onion named the Walla Walla Sweet. 1,200 acres are dedicated to this unique variety of onion.
Where Do Onion Plants Come From?
Many modern scientists and food historians believe that onions were first grown in central Asia, while other research suggests that they may have originated in Iran and West Pakistan.
Even though the true origin of onions is unclear, it is known that they have been found in cultures throughout history.
Wild onions are thought to have been a part of the human diet dating back to prehistoric times, well before written documentation or farming were ever-present within society.
Due to their popularity in England at the time, the pilgrims chose to bring onions with them on the Mayflower when they set sail. Once they reached America, they found that Native Americans had been growing and gathering wild onion varieties long before their arrival.
Though various wild onions were present upon their arrival, the pilgrims were able to successfully utilize the bulb onions they’d brought as a garden crop and harvest them to sell at market.
While there may not be a conclusive answer for where onions originated, it is safe to say that they have been a staple of the human diet longer than most other vegetables we eat today.
Where Do Onion Plants Grow Best?
Though onions have been shown to successfully grow across the world, there are some conditions under which they grow best.
Considered to be heavy feeders, onions will require a heavy dose of nutrients throughout their growing season, whether that be nutrients that exist in the soil or supplemental feeding.
The Columbia River Basin is a good example of an area that has naturally occurring fertile soil and a great place for onions to grow. Onions find the nutrients in the region preferential and they encourage the high yields that come from the area.
Along with requiring consistent nutrition, onions are considered a photoperiodic plant. This means that they will be sensitive to the amount of daylight they receive.
The region the onions are being planted will largely dictate which of the varieties will grow best. There are long-day, short-day, and day-neutral varieties that will each require different amounts of daylight.
Check out “Long Day Onions vs. Short Day Onions” to learn more about the difference between the onion types.
An area may also be able to accommodate more than one variety. California can accommodate daylight conditions for all three onion types, given the size and variance of daylight received throughout the state.
All things considered, it is safe to say that regardless of variety or area, onions will always grow best when their specific needs are met. Ample nutrition and sunlight will grow the best onions in an area as long as the preferences of the specific variety are known.
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