by Zack Davis, Somervell County Extension Agent
It is hard to say when the onion came into being. They were grown in Ancient Egypt, and eventually arrived in Rome and became known as the word onion (from the Latin word UNIO, which means large pearl). In Middle English, it became UNYON. The status of the onion rose after French Onion Soup was made popular by Stanislaus I, the former King of Poland.
The confusing part is that each variety needs a particular combination. For instance, a variety that needs many hours of summer light will not perform well in an area that receives fewer hours of light. Onion growers categorize onions in one of three ways: Short Day, Intermediate Day, and Long Day. The best way to insure success is to plant transplants from January through February in Texas Zones III – V (USDA Zones 8 and 9).
Before obtaining your plants, you may want to begin soil preparation. Onions are best grown on raised beds at least 4 inches high and 20 inches wide. Onions need a very fertile and well-balanced soil. Organic gardeners should work in rich finished compost, high in Nitrogen and Phosphorus with plentiful minerals. Spread lime if soil is too acidic. If using commercial fertilizer (10-20-10), make a trench in the top of the bed 4 inches deep, distribute one-half cup of the fertilizer per 10 linear feet of row. Cover the fertilizer with 2 inches of soil.
Onion plants are hardy and can withstand temperatures as low as 20 degrees F. They should be set out 4 to 6 weeks prior to the date of the last average spring freeze. When you receive live plants, they should be planted as soon as possible. They should be dry, do not wet them or stick their roots in soil or water. Unpack your plants and store them in a cool, dry place until you plant them. Properly stored onion plants will last up to three weeks. Do not worry if the plants become dry, the onion is a member of the lily family and as such will live for approximately three weeks off the bulb. As soon as they are planted, they will “shoot” new roots and green tops.
Onions are best grown on raised beds at least four inches high and 20 inches wide. Onion growth and yield can be greatly enhanced by banding a fertilizer rich in phosphorous (10-20-10) 2 to 3 inches below transplants at planting time. Make a trench in the top of the bed fours inches deep, distribute one-half cup of the fertilizer per 10 linear feet of row, cover the fertilizer with two inches of soil and plant the transplants.
Onions require a high source of nitrogen. A nitrogen-based fertilizer (ammonium sulfate or ammonium nitrate) should be applied at the rate of one cup per twenty feet of row. The first application should be about three weeks after planting and then continue with applications every 2 to 3 weeks. Once the neck starts feeling soft do not apply any more fertilizer. This should occur approximately 4 weeks prior to harvest. Always water immediately after feeding and maintain moisture during the growing season. The closer to harvest the more water the onion will require.