Mashua tubers

Mashua is a rare plant related to garden Nasturtium that can be grown as a decorative climbing ornamental or a food crop.

It is sometimes referred to as one of the “lost” Inca crops. Probably because it is listed in the book “Lost Crops of the Incas – Little-Known Plants of the Andes with Promise for Worldwide Cultivation” (available as PDF here). However, Mashua was never lost. It is still grown in the Andes region as a “minor” but quite nutritious food source.

Native to the high altitudes of the Andes, it grows well in cooler climates as well as in wet and even poorer soils. The plant also has an excellent reputation for resistance to many pests and diseases. Its hardiness and vigour makes it a quite interesting and useful crop, particularly if our climate continues to change with more storms etc.

Here in West Cork we grow it trellised in a sunny position in our polytunnel. It is very easy to grow. Plant the tubers in March to April in soil that is not too rich (don’t add dung that season) and harvest when the frost has killed the vines. You store tubers for the next planting in a pot or box with damp sand in a cool frost free environment.

We found that so far it grows best for us when we let it climb on a support like a climbing bean. It is vigorous, so be aware that it can shade other plants. In the Andes it is apparently also often grown on a mound letting it sprawl smother the competing weeds on the ground.

The main crop is the tubers but the leaves and flowers can be also used in salads like regular Nasturtiums. They have an interesting mild tangy flavour that is spicy like mustard greens or radishes with a pleasant undertone of something similar to almond.

The raw tubers have a much more pronounced tangy spiciness and they are often cooked which makes them milder. We prefer them oven roasted as a side dish, but allegedly they are also delicious in stews or as croquettes.

The dark skinned variety is new to us for 2026 and we find it prolific and with a slightly different texture and flavour profile compared with the yellow variety.

Each portion contains 6 tubers of various sizes. This should be plenty for multiplying the crop. Some sources says a single plant can grow clusters of tubers of up to 4 kg. However, so far we have had normal avg. yields of 1-2.5kg per plant in West Cork.