Bluebonnets are annuals that can be planted in spring or fall. Spring is best for seed germination. Fall planting is usually done when the bluebonnet plants have finished flowering, but some varieties may flower earlier than others and will produce seeds even if they are killed by frost. Bluebonnets do not require temperatures above 20oF (7oC). They need sunlight to become established and thrive once they get started. If you plan on growing them outside of their native range, you should provide some shade. The warmer it gets, the more quickly bluebonnet flowers bloom…weather permitting!