ISSUE 74, THE BOOK OF RARER VEGETABLES, Part 3: Oca Root
Oca Root
The United States never embraced this South American root vegetable, despite its extensive cultivation in the Andes. Other parts of the world were not so shy. New Zeeland in the 1860s imported it, began cultivating it, and made it a table regular under the name “New Zeeland Yam.” It is not biologically a yam. It is a perennial plant with underground tubers—Oxalis tuberosa—extensively cultivated by the native Quechua prior to European contact and taken up as a staple crop by European settlers. It remains the second most popular tuberous vegetable in cultivation in Bolivia and Peru. Various strains exist, each sporting a different color: red, pink, orange, tan, apricot.
The flavor of Oca is surprising, with a citrus tang, a fresh acidic kiss when eaten fresh and raw. If the tubers undergo a curing process, that tempers the acid, making it more like a a potato. Cooked (they are boiled or baked), the oca have “a softer texture with a slightly sweet and nutty taste.” Slices of Oca cut from fresh roots often adorn salads in the Andean region. Pickled they are quite sprightly, more interesting in flavor than pickled Jerusalem Artichokes (which have a similar crisp texture.) Another favorite preparation is deep fried Oca Chips. The leaves of the Oca plant are also edible and used as a pot herb in South America.
George Wythes in The Book of Rarer Vegetables (1906) described two strains of the multitude that began being cultivated on a small scale in the 19th century: “The tubers of the Oxalis are produced freely and are, when well grown, of the size of a large walnut, having a smooth skin and eyes in profusion, and a yellow skin in one case and a dull reddish on in the other. The tubers are long and pointed, somewhat like the Chinese Artichoke.” (71) The similitude to the Chinese Artichoke of some varieties of Oca is striking, sharing the same knobbed, crenulated body. Yet the Oca is colored, the Chinese Artichoke bone white.
One of the great projects of counter-culture gardening that took place in the 1970s in the Pacific Northwest was Dr. Alan Kapular’s breeding beds maintained at a commune in Oregon. He collected every native landrace he could obtain, grew them out, and preserved seeds. Many of the strains available in North America derive from his collection. He made the Oregon-Washington area the one place in the United States where Oca can be encountered on the produce stand.
If you want to try growing them out, starter sets are available from raintree nursery: