Mashua (Tropaeolum tuberosum): Fresh or Cooked Delicacy of Andes Tuber

Summary: Mashua (Tropaeolum tuberosum) is a New World edible tuber, native to the Andes, that is served as a fresh or cooked delicacy.

Flowering mashua, in full growth at time of tuber harvesting, altitude of ca. 3,000 meters, near Quito, Provincia de Pichincha (Pichincha province), north central Ecuador; Germplasm collection of Instituto Nacional de Investigaciones Agropecuarias (INIAP; National Institute for Agricultural Research), Estación Experimental Santa Catalina (EESC; Santa Catalina Experimental Station); May 1990: Michael Hermann, CC BY SA 4.0 International, via Wikimedia Commons

Tropaeolum tuberosum is an edible tuber in the nasturtium genus, Tropaeolum, which is the only genus in the Tropaeolaceae family.

The New World tuber's most widely used common name is mashua, a Quechua word of unknown meaning. Primarily spoken in South America's central Andean region, Quechua stands out as the most widely spoken language of indigenous peoples of the Americas.

Mashua's official description is credited to Spanish botanists Hipólito Ruiz López (Aug. 8, 1754–ca. 1816) and José Antonio Pavón Jiménez (April 22, 1754–1840). The two expeditionary botanists based their description in 1802 upon a specimen that they collected in Peru during the Botanical Expedition to the Viceroyalty of Peru (Expedición Botánica al Virreinato del Perú). The expedition was commissioned by Carlos III (Jan. 20, 1716–Dec. 14, 1788), fifth Bourbon King of Spain and the Spanish Indies (Aug. 10, 1759–Dec. 14, 1788), and conducted from April 1778 to March 1788.

A New World native, cultivated and wild forms of mashua are found in the high Andes from Colombia southward to northwestern Argentina. Located in the Jauja Valley in Peru's Central Highlands, Huachumachay Cave has yielded the first archaeological evidence of mashua, dating from 650 to 1350 A.D.

Included among designs of Andean tubers on pottery from Pacheco in southern Peru's lower-middle Nazca Valley are beautiful depictions of mashua. The location of the Nazca Valley, from Peru's Pacific Coast inland to the Andes Mountains, suggests the possibility of mashua not only as a highland staple but also as a coastal crop.

Despite its desirable attributes as hardily prolific and as resistant to frost and pests, mashua suffers from a rustic connotation due to its long-time cultivation in high-altitude remoteness.

Current Andean cultivation tends to occur on small-scale plots, with Peru emerging as the tuber's largest producer. In Ecuador, mashua is grown in isolated areas of La Sierra, the highland geographic region stretching centrally from north to south. Colombia's cultivation is restricted to Boyacá, the country's north central department. Only Argentina's northwestern provinces grow mashua, both for food and as an ornamental.

Although seeming to suffer from declining production in its native habitats, mashua is experiencing a surging interest as an introduced crop in new ecosystems, especially in New Zealand, and also in the Pacific Northwest in the United States.

Although traditionally produced as an annual, mashua is actually a perennial plant. Annual propagation entails spring planting of seed tubers.

Mashua tubers display a wide range of colors that is reflected in varietal common names. Orange predominates in zanahoria-añu (“like a carrot”) and zapallo-añu (“like a pumpkin”) varieties. Phutilla-añu and Puca-añu varieties are red. Yurac-añu applies to white tubers Yawar waqac ("tears of blood") tubers present a yellow background covered in red stripes.

Mashua is a completely edible plant, from its above-ground leaves, palm-shaped in 3 to 5 lobes, and flowers, brilliantly hued in reds and yellows, to its below-ground, colorfully blushing tubers. The pungency of raw mashua tubers, described as peppery and likened to radishes (Raphanus sativus), mellows with cooking.

Fresh tubers, thinly sliced, contribute a peppery taste to fresh salads. Tubers stewed with herbs, meats, and other vegetables are a favored recipe in the Andes. A dessert of the cooked tuber, soaked in molasses, is popular in Bolivia and Peru.

Mashua's raw pungency derives from isothiocyanates, natural compounds prized as natural repellents of gophers and other garden pests. Traditionally, mashua is intercropped with other root vegetables, such as oca (Oxalis tuberosa) and ulluco (Ullucus tuberosus). In Colombia, Ecuador and Peru, mashua is planted, as a companion plant for potatoes (Solanum tuberosum), in border rows to repel potato pests.

As a hardy, prolific tuber with desirable attributes of frost resistance and pest repellence, mashua qualifies as a welcome companion plant in gardens. Mashua's qualities as a garden plant have been acknowledged by way of the Award of Garden Merit (AGM), bestowed upon a cultivar, Tropaeolum tuberoseum var. lineamaculatum 'Ken Aslet,' in 1993 by the Royal Horticultural Society.

As a completely edible plant, mashua rewards gardeners with visual appeal and satisfying deliciousness as fresh and cooked ingredients at mealtime.

"Sample of clonally propagated mashua cultivars, in Peru"; 1995: Michael Hermann, CC BY SA 4.0 International, via Wikimedia Commons

Acknowledgment

My special thanks to talented artists and photographers/concerned organizations who make their fine images available on the internet.

Image credits:

Flowering mashua, in full growth at time of tuber harvesting, altitude of ca. 3,000 meters, near Quito, Provincia de Pichincha (Pichincha province), north central Ecuador; Germplasm collection of Instituto Nacional de Investigaciones Agropecuarias (INIAP; National Institute for Agricultural Research), Estación Experimental Santa Catalina (EESC; Santa Catalina Experimental Station); May 1990: Michael Hermann, CC BY SA 4.0 International, via Wikimedia Commons @ http://commons.wikimedia.org/wiki/File:Flowering_mashua_Quito_May_1990.tif

"Sample of clonally propagated mashua cultivars, in Peru"; 1995: Michael Hermann, CC BY SA 4.0 International, via Wikimedia Commons @ http://commons.wikimedia.org/wiki/File:Mashua_tuber_diversity_Peru_(Tropaeolum_tuberosum).JPG

For further information:

Grau, Alfredo; Ramiro Ortega Dueñas; Carlos Nieto Cabrera; Michael Hermann. Mashua (Tropaeolum tuberosum Ruiz & Pav.). Promoting the Conservation and Use of Underutilized and Neglected Crops #25. Lima, Peru: International Potato Center; Rome, Italy: International Plant Genetic Resources Institute, 2003.
Available via Biodiversity International @ http://www.bioversityinternational.org/uploads/tx_news/Mashua__Tropaeolum_tuberosum_Ru%C3%ADz__amp__Pav._880.pdf

National Research Council (U.S.). Lost Crops of the Incas: Little-Known Plants of the Andes with Promise for Worldwide Cultivation. Washington DC: National Academy Press, 1989.

Ruiz, Hippolyto, and Josepho Pavon. Flora Peruviana, et Chilensis, Sive Descriptiones, et Icones Plantarum Peruvianarum, et Chilensium, Secundum Systema Linnaeanum Digestae, Cum Characteribus Plurium Generum Evulgatorum Generum. Plates XLIII-CCCXXV. Madrid: Typis Gabrielis de Sancha, 1798 – 1802.
Tropaeolum tuberosum (plate CCCXIV) available via Biodiversity Heritage Library @ http://biodiversitylibrary.org/page/675123

Van Houtte, Louis. Flore des Serres et des Jardins de l'Europe. Tome cinquième. Gand, Belgium: Louis Van Houtte, 1849.
Tropaeolum tuberosum illustration by Louis Constantin Stroobant (1814 - 1872) available via Biodiversity Heritage Library @ http://biodiversitylibrary.org/page/16233987