Growing Onions in the Home Garden Horticulture Growing Onions in the Home Garden Onions are one of the most popular vegetables in the home garden. They can be grown for green onions and dry bulbs. Onions are easy to grow. They perform best in well-drained, slightly acidic, fertile soils in full sun. Heavy soils can be improved by incorporating organic, such as compost or peat, into the soil.
Onions require higher fertility levels than most other vegetables.
Four to five weeks after planting, sidedress with additional fertilizer. Sprinkle 1 pound of an all-purpose garden fertilizer per 100 feet of row. Place the fertilizer in a narrow band about 2 to 3 inches from the base of the onion plants. An important aspect of onion development is photoperiod or day length. Photoperiod, along with temperature, control bulb formation.