In botany, a whorl or verticil is a whorled arrangement of leaves, sepals, petals, stamens, or carpels that radiate from a single point and surround or wrap around the stem or stalk. A leaf whorl consists of at least three elements; a pair of opposite leaves is not called a whorl. For leaves to grow in whorls is fairly rare except in plant species with very short internodes and some other genera.
The morphology of most flowers is based on four types of whorls:
- The calyx: zero or more whorls of sepals at the base
- The corolla: zero or more whorls of petals above the calyx
- The androecium: zero or more whorls of stamens, each comprising a filament and an anther
- The gynoecium: zero or more whorls of carpels, each comprising an ovary, style, and stigma
A complete flower has all four whorls: sepals, petals, stamens, and pistil from base to top. The innermost whorl in a bisexual flower is the gynoecium, which contains the gamete-producing organs in the flower.
