- Perennial green leaf
- Perennial vegetables
- Edimentals
Oca: New Zealand Red
Oxalis tuberosa
Oca is compact, bushy perennial with clover-like leaves that produces edible tubers and leaves
PLANT TYPE Vegetable
PLANT HABIT Replant perennial
USES Culinary, Ornamental
DESCRIPTION
New Zealand Red Oca (also known as New Zealand Red Yam or Uwhiuwhiu) is a cultivar of Oxalis tuberosa, a tuber crop native to the Andes that became popular in New Zealand after arriving on whaling ships in the mid-1800s. Despite the name, it is not a true yam but is related to the wood sorrel family.
Oca is compact, bushy perennial with clover-like leaves that also serve as an edible green vegetable. It thrives in temperate climates, tolerates cool conditions, and is typically harvested in autumn after the foliage dies back. This variety has been tried and tested in the UK to be found hardy and well adapted to British conditions.
Produces attractive bright red tubers with a shiny, ribbed surface that does not require peeling. They can be eaten raw in salads with a slightly tart, citrus-like tang, which transforms into a lemony sweetness when cooked. The cooked texture is like a potato and they should be cooked like potatoes.
Tubers are purportedly high in carbohydrates, folate, and vitamins A and B6.
RECOMMENDED LOCATION Pot, Kitchen garden, Forest garden, Wildlife garden, Ornamental garden
Aspect Full sun, Moist full sun
Height 0.3-0.6m
Spread 0.6-0.9m
Hardiness Hardy in the UK
Management and care At the end of the season there is one peculiarity about growing Oca that is important to understand. When the leaves have died of frost and the plant looks to have died off, the succulent stems are actually still alive. It is at this late point that the plant moves any remaining energy and nutrition from its upper parts into it’s tubers, which grow significantly at this time. As rule of thumb, wait at least two weeks after leaves have fully been frosted to allow the tubers to grow before harvesting. Usually in the UK that’s just in time for Christmas!
Origin/history
Oxalis tuberosa is a perennial herbaceous plant that overwinters as underground stem tubers. These tubers are known as uqa in Quechua, oca in Spanish, yams in New Zealand and several other alternative names. The plant was brought into cultivation in the central and southern Andes for its tubers, which are used as a root vegetable. The plant is not known in the wild, but populations of wild Oxalis species that bear smaller tubers are known from four areas of the central Andean region. Oca was introduced to Europe in 1830 as a competitor to the potato, and to New Zealand as early as 1860.
In New Zealand, oca has become a popular table vegetable and is called yams (although not a true yam). It is available in various colors, including yellow, orange, pink, apricot, and traditional red.
