It is time to start thinking about planting onions in your garden. It will be time before we know it.
Care of Transplant - When you receive live plants, they should be planted as soon as possible. If you are unable to plant these plants right away, remove the onion plants from the box and spread them out in a cool, dry area. The roots and tops may begin to dry out, but do not be alarmed; the onion is a member of the lily family, and as such, will live for approximately three weeks off the bulb. The first thing that the onion will do after planting will be to shoot new roots.
Preparing the Soil - 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 four 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.
Planting - Set plants out approximately one inch deep with a four inch spacing. On the raised bed, set two rows on each bed, four inches in from the side of the row. Should you want to harvest some of the onions during the growing season as green onions, you may plant the plants as close as two inches apart. Pull every other one, prior to them beginning to bulb, leaving some for larger onions. Transplants should be set out 4 to 6 weeks prior to the date of the last average spring freeze.
Harvesting and Storage - Onions are fully mature when their tops have fallen over. After pulling from the ground, allow the onion to dry, clip the roots, and cut the tops back to one inch. The key to preserving onions and to prevent bruising is to keep them cool, dry and separated. In the refrigerator, wrapped separately in foil, onions can be preserved for as long as a year. The best way to store onions is in a mesh bag or nylon stocking.
Place an onion in the bag and tie a knot or put a plastic tie between the onions and continue until the stocking is full. Loop the stocking over a rafter or nail in a cool dry building and when an onion is desired, simply clip off the bottom onion with a pair of scissors or remove the plastic tie. Another suggestion is to spread the onions out on a screen which will allow adequate ventilation, but remember to keep them from touching each other.
As a general rule, the sweeter the onion, the higher the water content, and therefore the less the shelf life. A more pungent onion will store longer so eat the sweet varieties first and save the more pungent onions for storage.
Lonnie Jenschke is an Erath County extension agent.