Mashua
Tropaeolum tuberosum
A climbing nasturtium with peppery, striped tubers that form as days shorten; pests tend to leave it alone.
Hardiness: zones 7 to 10
Light: full sun to part shade
Size: about 6 ft tall, 3 ft wide
Harvest: November to December
From: Andes
Here: Hardy in the Lake Erie shore climate (zone 6b to 7a), so it can live outdoors in the ground.
Good for: food, pollinators.
Native to: Andean highlands. Hardy in zones 7 to 10.
The story
Mashua, the Andean nasturtium, was grown by the Inca as the fourth tuber beside potato, oca and ulluco; soldiers were said to be fed it to curb desire, and it is still planted with potatoes as a pest-repelling companion on Andean terraces.
Planting
Full sun or part shade, loose rich soil, a cool season, and a trellis; plant tubers after frost. It climbs 6 feet.
Growing
Water steadily and keep cool; it tubers as days shorten in autumn. Mulch.
Harvest and use
Dig after frost kills the tops; cook thoroughly, since raw tubers are peppery. Roast, boil, or freeze and sun-sweeten the Andean way.
What to watch for
Heat, and early frost.
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More perennial vegetables, greens and herbs
General guidance, not professional advice. Conditions vary by yard and year; for local specifics ask your county extension office. Never eat a wild plant you cannot identify with certainty. Traditional uses are shared as history, not medical advice. © 2026 Sean Priest · Irie Orchard. Terms & credits · Privacy · Home