B. giganticaulis

Culture

Original Botanical Description or Link to

Herb perennial, evergreen, to 4 m tall, dioecious. Rhizome short, stout, nearly unbranched, reddish brown, to 12 cm thick. Stem erect, reddish brown or green, glabrous, internodes to 5 cm thick, with many longitudinally fusiform whitish spots, cross section of stem often reddish brown, nodes notably enlarged, to 7 cm thick, with unequally oval to round whitish spots, many shrubby branches on the upper part of main stem. Stipule long-triangular, light green or pinkish green, 9–25 × 2–8 mm, glabrous, margin entire, dorsal ridge pinkish, apex acuminate with arista 4–6 mm long. Petioles green, pink to red, glabrous, 7–22 cm long, 1–3 mm thick. Leaf blade ovate-lanceolate to lanceolate, 4–19 × 0.8–8 cm, adaxial green, muriculate to nearly glabrous, adaxial veins slightly concave; abaxial greyish green, veins usually red, convex, main veins sparsely and obliquely strigose; base obliquely cordate, margin shallowly and remotely denticulate, apex long caudate; Inflorescence dichasial cyme, axillary, short, 3–5 cm long, unbranched to branched once, rachis glabrous, green, pinkish green to red, base usually red-brown, 7–15 mm long, 1–1.5 mm thick, 3–11 male flowers or 1–5 female per inflorescence. Bract often caducous, pinkish green, long triangular, glabrous, ca. 6 × 3 mm, apex acuminate; bracteoles smaller. Staminate flower: pedicel glabrous, white, whitish or pinkish green, 10–14 mm long, ca.1 mm thick; corolla 18–24 mm in diameter; tepals 4, subequal, glabrous, outer 2, obovate, 9–14 × 6–9 mm, apex obtuse, adaxially white and middle-upper part abaxially pink, or pure white for some individuals, longitudinal veins unapparent; inner 2, pure white, obovate to obovate-lanceolate, 8–13 × 5–7 mm, apex obtuse; androecium nearly actinomorphic, ca. 5 mm long, 6–7 mm in diam; stamens 48–60, filaments free, 1–2 mm long; anther yellow, 2–3 mm long, apex obtuse or nearly so. Pistillate flower: pedicel white or green-white, 6–12 mm long, 0.8–1 mm thick; corolla 20–25 mm, tepals 6, rarely 4, glabrous, outer 3 (rarely 2), obovate or long obovate, thick and rigid, 12–18 × 7–10 mm, adaxial surface nearly white, distinctly concave, abaxially pink on middle-upper part, inner 3 (rarely 2), obovate-lanceolate to oblanceolate or long elliptical, slightly narrower than outer tepals, 10–19 × 6–8 mm, white, glabrous, apex obtuse; styles + stigmas 5 mm long, 7–8 mm wide; styles 3, free; stigmas yellow, nearly U-shaped, each side spirally twisted 1.5 circles; ovary pink or green, with white convex spots; placentation axile, 3-loculed, each placenta 2-branched. Peduncle green to pinkish green, glabrous, 8–12 mm long, ca. 1 mm thick. Fruit red, pink or green, glabrous, triangular-gyroscopic, 8–11 × 1–12 mm wide, concave between two placentas, wingless to occasionally short ridged, apex with beak 3–4 mm long. Flowering Jun.–Oct., fruiting Jul.–Dec.