Brussels sprouts (scientific name: Brassica chinensis L.) is Cruciferae, brassica annual or biennial herbs, up to 70 cm high, glabrous, thick roots, hard, basal leaves obovate or broadly obovate, solid, dark green, glossy, petiole with or without a narrow margin; racemes terminal, paniculate; flowers light yellow, pedicels fine, and flowers as long or shorter; Sepals oblong, white or yellow; petals oblong, rounded at tip, veined, long horned fruit linear, petals with distinct midrib and anastomosing lateral veins; beak fine at tip, seeds globose, purplish-brown, honeycombed. blooms in April, fruits in May.
Basal leaves obovate or broadly obovate, 20-30 cm long, firm, dark green, glossy, base tapering into a broad stalk. Entire or with inconspicuous crenate or undulate teeth. Midvein white. Up to 1.5 cm wide, with multiple longitudinal veins; petiole 3-5 cm long, with or without narrow margins; lower cauline leaves similar to basal leaves, base tapering into a petiole; upper cauline leaves obovate or elliptic, 3-7 cm long, 1-3.5 cm wide, base clasping, broadly spreading, with pendant auricles on both sides, entire, faintly pruinose.
Racemes terminal, paniculate; flowers pale yellow, ca. 1 cm, up to 1.5 cm after pollination; pedicels fine, as long as or shorter than flowers; sepals oblong, 3-4 mm, erect spreading, white or yellow; petals oblong, ca. 5 mm, rounded at the tip, veined, broadly clawed. Long-horned fruit linear, 2-6 cm long, 3-4 mm wide, hard, glabrous, petals with conspicuous midrib and anastomosing lateral veins; beak apically thin, base broad, 8-12 mm long; fruiting pedicel 8-30 mm long. Seeds globose, 1-1.5 mm in diam., purple-brown, with honeycomb pattern. Fl. April, fr. May.