Cultivation and propagation couldn't be easier. During this time fertilization is ceased and plants are watered sparingly. Although pregnant onions tolerate a wide range of light conditions, in Florida they perform best in bright indirect light. Protection from afternoon sun is a must. Propagation is accomplished vegetatively by removing offsets from the mother plant or by sowing the shiny black seeds in spring.
Seedlings quickly form bulbs and flowering commences in the third year.
O. longibracteatum is hardy in USDA zones 9 through 11.