Oca

Imagine a tuber with the texture of water chestnut and the flavor of a starchy apple. This cousin of wood sorrel is called oca.

Oca tubers (Laurenjm) CC BY-SA 3.0

Oca (Oxalis tuberosa) is a perennial edible that overwinters as underground stems similar to sweet potatoes. Oca has been a dietary staple of the Andes region for centuries, and you can grow it at home and enjoy it raw, cooked, or pickled. Highly nutritious, oca is a very flexible plant. The tubers, leaves, and stems are all edible.

Oca description

The tubers are small and nubby. To me, they almost look like turmeric rhizomes. They can be orange, pink, or yellow, but most commonly are red. The leaves look a lot like Bermuda buttercup. Flowers appear after 3 or 4 months. Oca starts producing tubers when temperatures drop into the low 50s (°F) and the days get shorter.

Oca plant (Izawa Ryu) CC BY-SA 4.0

How to grow oca

These plants grow best in cool, wet weather. When shopping for oca tubers, opt for sweet oca over sour oca. Both are edible, but the names pretty much say it all. Plant seed tubers two to three inches deep and 24-36” apart.

Like yacón, another Andean native, these plants grow well in poor soil and harsh climates, but need a long growing season. Each oca plant can produce up to three pounds of tubers yearly, though one pound is more likely. 

Oca pests and diseases

Nematodes and weevils can damage your oca crop. Some viral diseases may also appear, but you can reduce most problems with a three-year crop rotation.