How do Vidalia onions grow?
Most onion plants are biennials. This means a plant grows vegetatively during the first year and fruiting and dying occurs during the second year. When fully grown they consist of a bulb, leaves, and roots. The leaves are long, slender hollow cylinders that grow upright. At the base they thicken to form a bulb, the part of the plant that people eat most frequently. The bulb is enclosed in a thin papery covering made up of dried outer scale leaves. Depending on the amount of daylight needed to begin the bulb formation, onions are classified as short day onions and long day onions. Short day onions grow best in the Southern United States and require 10 to 11 hours of daylight. All onion plants require an average temperature greater than 60 degrees to form a bulb.
