Mashua1 (Tropaeolum tuberosum) is probably the Andean region's fourth most important root crop—after potato, oca, and ulluco. It is a hardy plant, and in the poorest regions, where pesticides and fertilizers are too costly to use, mashua is sometimes the prevalent root crop. Its tubers can be found in almost any rural Andean market.
Mashua (pronounced mah-shoo-ah or mah -shwah) is closely related to the garden nasturtium, an Inca ornamental that is now well-known throughout most temperate zones. In fact, these two beautiful plants are often found together in Andean gardens, one grown for its edible tubers, the other for its pretty and edible flowers.
Among Andean tubers, mashua is one of the highest yielding, easiest to grow, and most resistant to cold. It also repels many insects, nematodes, and other pathogens, thus making it a valuable plant to intercrop with other species.2 Yet, in spite of its productivity, pest resistance, and popularity, mashua is not widely commercialized—either in its native land or elsewhere.
The tubers—about the size of small potatoes—have shapes ranging from conical to carrotlike. Eaten raw, some have a peppery taste—reminiscent of hot radishes. But when boiled, they lose their sharpness and become mild—even sweet. Boiled mashua is used to add variety to other foods. It is popular in soups. In Bolivia and some parts of Peru, it is topped with molasses and frozen to make a special dessert.
Like oca, maca, ulluco, and bitter potatoes,3 mashua can provide food at high elevations. This frost-tolerant crop is cultivated in small plots on hillsides—especially on ancient terraces—in cool and moist upland valleys of Argentina, Colombia, Ecuador, Peru, and Bolivia. Peru, it is reported, grows 4,000 hectares of mashua each year.
Within Andean communities, some families choose to plant mashua