Plant sets in mid-March or plants or sow seed in early April. Spacing Onions may be grown in rows as close as 15 inches, with individual plants spaced 2-4 inches in the row, depending on the size of the bulb. Plant sets 1-1 inches deep, and plant transplants about the same depth. Care Onions have a shallow, inefficient root system and need regular watering and fertilizing for best results. They compete poorly with weeds and other crops.
Weed control is essential to reduce competition.
Watering may be reduced near the harvest period, but regular timely watering is needed until the tops begin to fall over. Large vigorous plants are essential for large bulbs with high yields. Harvesting Onions are ready for harvest when the tops begin to weaken and naturally fall over. This is a signal that the bulbs are as big as they will get. Pull or dig the onions and store in a warm, dry, shaded location for 2-4 weeks until the tops and necks are completely dry.