Onions are thought to have been around for thousands of years. Many believe that they originated in central Asia, and others suggest that they were first grown in the Middle East. Either way, onions have been cultivated by many different civilizations and areas for over 5000 years. Onions are said to be one of the earliest cultivated crops because they were easy to transport, easy to grow, and lasted longer than other fresh fruits and vegetables. Onions were also used to sustain life. They helped quench thirst, and could be easily preserved for later use when food sources were scarce. Early writings and documents describe onions as being used in art, medicine, and mummification as well as for food.
In the United States, farmers plant about 125,000 acres of onions, and harvest about 6.2 billion pounds of fresh onions each year. Although onions are grown in more than 20 states, the top three onion areas in the United States are California, Idaho-Eastern Oregon, and Washington.
Onion farmers begin by tilling their fields and preparing them prior to planting season. The fields are fertilized and prepared for the coming growing season that lasts 5-6 months. The seed beds are harrowed flat and the planting begins. Once onion seeds are planted, they are fertilized and watered. About 2/3 of the onion actually grows on top of the soil. The bulb of the onion grows at a rate that is directly reflective of the length of the day and the latitude at which it is grown. Irrigation is stopped according to the size and maturity of the plants. Farmers know when the onions reach maturity because the tops will naturally fall over.
Using a special attachment for the tractor, onions are lifted out of the ground to break the root system. Lifting is done when the temperature is less than 90 degrees. Onions are then left to dry on top of the soil for about 2 weeks. Onion tops are mechanically removed and the onions are placed in large rows, ready to harvest. Onion loaders load the onion bulbs into trucks to be transported to storage or packing facilities.
At the storage facilities, onions are loaded into bins or bulk storage. Onion bins are slotted wooden boxes that are about 4ft. by 6 ft. and 30 inches deep. Bulk storage is a huge pile of onions, 9 to 14 ft. tall. During storage air fans constantly blow air through bins and piles of onions to cure and dry the bulbs so that they do not go bad during storage or processing.
The onions arrive at the packing facility and are placed on the conveyor belts that take them throughout the facility. They go through the sorting table, where bad onions, and other debris, are removed. Quality assurance personnel are constantly checking bags and boxes of packed onions to ensure that they are of the highest quality. This inspection process helps certify that only the very best onions reach the consumer. The onions are then sized and sorted into boxes and bags of varying weights. The boxes and bags of onions are then loaded onto pallets and shipped to grocery stores and restaurants around the world.