If heavy rains leach out the N, apply another sidedressing when plants are about half grown. Heavy N application later in the season may result in necks that are too large. Seed should be spaced 2 to 4 inches in the row, depending on desired size for market. Transplants should be spaced 3 to 4 inches apart in the row. Planting on shaped beds will ensure better drainage and make possible the operation of pulling the soil away from the bulbs at time of maturity to hasten drying and facilitate digging.
Shallow cultivation is necessary to break crusts.
Downy mildew, powdery mildew and tip burn are common onion diseases in North Carolina. Irrigating a few days before harvest will make digging easier. Avoid excess irrigation or waiting too late because such irrigations can cause cracking. About a month before harvest, it is best to start working the soil away from the bulbs. This process should involve 2 or 3 cultivations so that about 7 to 10 days before harvest time, the bulb is about one-third above ground, which hastens bulb and neck drying.