Cooked tubers appear in dry coastal tombs dated at 2500 B.C., indicating both an ancient origin and the fact that the roots were esteemed highly enough to be carried all the way from the highlands.
Description. Achira is a perennial monocotyledon with clumps of purple fleshy stems and multibranched subterranean rhizomes. The large (30 cm × 12 cm) leaves are entire with a thick midrib. They are dark green, tinged with reddish brown or with reddish brown veins on the upper surface and purple on the underside. Achira grows to about 2.5 m in height. Dwarf forms are also known.
The beautiful, bright-red to orange bisexual flowers occur in long terminal clusters standing above the leaves. Some plants produce round, black seeds, but farmers propagate the plant exclusively by vegetative means.
The rhizomes may reach more than 60 cm in length; a single stool has weighed 27 kg. A single rhizome may consist of 12 segments representing five generations of growth. If the plant is defoliated, the rhizome will put up new shoots and leaves.
Horticultural Varieties. In the Andes, two types are recognized: verdes, which has off-white rhizomes and bright green foliage, and morados, which has rhizomes covered with violet-colored scales. There are many variations in foliage color, stem height, rhizome size, earliness of flowering, and amount of seed production. No cultivars have been selected outside the Andes.
A collection of about 30 Peruvian clones is maintained at the University of Ayacucho.
Daylength. The plant is apparently daylength neutral, and it appears to grow under a broad range of light environments.18
Rainfall. The plant withstands rainfalls from 250 to 4,000 mm, a huge range. At the lower levels, however, plants may be stunted and low-yielding. Achira does best with moderate, evenly distributed rainfall, although its rhizomes can survive periods of either flooding or drought. In Hawaii, annual rainfall of 1,120 m is said to be adequate.
Altitude. Sea level to 2,900 m (at the equator).
Low Temperature. Normal growth occurs at temperatures above