Brussels sprouts grow best in cool weather and are usually planted in late spring or early summer for a bountiful fall harvest. In Washington State, Brussels Sprouts are usually available from October through March.
Brussels sprouts are a member of the cabbage family and cultivated for its leafy green buds that resemble tiny cabbages. The name comes from the fact that they were widely cultivated in Brussels, Belgium in the 16th century.
ref: Fruits and Veggies More Matters, University of Illinois Extension
Educational materials:
- Brussels sprouts video - from Oregon Harvest for Schools