Mashua

Mashua (Tropaeolum tuberosum), also called isaño, añu or cubio, is a hardy Andean tuber crop grown from 2,400-4,300 m in Peru, Bolivia, Ecuador and Colombia, and at sea level in cool maritime climates like coastal New Zealand. A relative of the garden nasturtium, it is famously rustic: no pest or disease seriously constrains it, foliage tolerates light frost, and it thrives on the residual fertility left after a fertilized potato crop. Plants form a dense, weed-smothering ground cover whose twining stems can climb past 2 m with support. The peppery tubers, among the richest known plant sources of glucosinolates, are traditionally sweetened by a few days of sun-curing before eating. Mashua is a strict short-day crop: tubers form only once day length drops below about 12 hours, and the crop needs 6-9 months in the ground, so site and season matter more than feeding. No hydroponic production has been published; all verified production is in well-drained soil.