How to Plant
In your raised beds, plant the onion plants about one inch deep - 5 inches apart. If you like to harvest green onions for salads or other dishes, plant the plants about three inches apart. Pull every other one for green onions, leaving the others five to six inches apart to grow into large whole onions.
Fertilizing and Growing Care
Incorporated a balanced fertilizer such as 10-10-10 or 10-20-10 into soil at planting. About a month after planting, feed them with 21-0-0 Ammonium Sulphate onion fertilizer at a rate of 1 cup per 20 feet of row. Repeat this process every 3 to 4 weeks. Always water immediately after feeding. As plants reach full size and maturity, the soil can be allowed to become more dry. If possible avoid watering within two weeks of expected harvest time (you can tell by their necks become softer). This will increase storage time.
When to Harvest & How to Store
When the tops of the onions have fallen over they are fully mature. Pull the onions from the ground and allow to dry. Cut the tops of the onion after it has dried, also trim the roots. To make the onions last as long as possible, store them in a dry cool place and keep them from touching. The two best methods are: 1) wrap each onion in newspaper to keep them from touching. 2) Use old stockings. Drop an onion in the end of the stocking, tie a knot just above it, then drop another onion into the stocking. Repeat this until the stocking is full. When full, hang in a cool dry place.