Herbs, annual or perennial, usually glabrous. Roots sometimes tuberous. Stem often climbing. Stipules sometimes present, especially in seedlings. Leaves alternate, simple; petiole long, often twining; leaf blade peltate or palmately lobed or divided. Flowers solitary axillary, large, ebracteate, long pedicellate, bisexual, zygomorphic, hypogynous. Sepals 5, imbricate, upper (posterior) 1(or 3) extended into a long nectariferous spur. Petals 5, sometimes fewer by abortion, yellow, orange, blue or purple, imbricate, clawed; 2 upper (posterior) petals larger and connate with spur, other 3 usually smaller and inserted in the opening of spur. Stamens 8, 2- verticellate, free, unequal, nearly included; anthers 2-celled, dehiscence by longitudinal slits. Pistil 1, carpels 3, syncarpous, ovary superior, 3-loculed, placentation axile, 1 ovule per locule, pendulous from axile apex, anatropous; style 1, apical; stigma linear, 3-lobed. Fruit schizocarpic, separating into 3 one-seeded mericarps, fleshy or dry. Seeds exalbuminous, embryo straight.

One genus and about 94 species

Tropaeolum majus