Plants erect or occasionally ascending annual, up to 3 m tall in some cultivated plants but much short in wild plants, often reddish-tinged in whole or throughout; Stems stout, simple to much branched, glabrous or with long multicellular hairs, these more abundant in the upper portion of the stems. Leaves with petioles to 15 cm long, scarcely longer than the blades; blades 3-19 (-30) cm long, 1.5-8(-12) cm wide, broadly lanceolate to rhomboid, lower surfaces glabrous or thinly pilose on the margins and over the primary venation. Inflorescences axillary and terminal "spikes" of cymose flower clusters of mixed male and female flowers these increasingly congested distally, terminal inflorescences single "spikes" or much branched panicles up to 45 cm long and 25 cm wide, the terminal "spike" often somewhat nodding. Female flowers with 5 tepals; tepals 1.5-3.5 mm long, lanceolate oblong, acute-aristate to blunt and aristulate; stigmas (2-)3. Capsules subglobose to ovoid-urceolate, 2-3 mm long, circumscissile, tops with a with small, smooth to inflated or wrinkled beak; seeds faintly reticulate, lenticular.
Amaranthus hybridus has two subspecies. They differ as shown:
1. Style bases and upper part of the ovaries not swollen, giving a narrow, firm beak; inner perianth segments of female flowers usually obtuse; longer bracteoles of the female flowers usually 1-1.5 times the length of the perianth ..... Amaranthus hybridius subsp. cruentus
1. Style bases and upper part of the ovaries swollen, giving an inflated beak; inner perianth segments of the female flowers usually acute; longer bracteoles of the female flowers about twice as long as the perianth .... Amaranthus hybridius subsp. hybridus
The Flora of Somalia states that Amaranthus hybridus subsp. cruentus had been found, probably on wasteland, in region S3. It is also present in Hargeisa (N1), often as a weed of paved areas