We commonly call Oca the New Zealand Yam, they are a small carrot coloured tuber that grows well in cool to temperate climates. They originally come from South America and the botanical name is Oxalis tuberose. They grow in cooler areas and are used as a vegetable crop. They are cooked in a similar manner to potatoes.
How to grow Oca
The plant itself is low growing and bushy in habit, it only reaches around 50cm in height at best.
This is a cool climate plant, although it comes from South America, it grows at altitudes.
So how cold a climate, they will grow well in the UK.
These are a vegetable that take around 6 months to produce good sized tubers, and this is where the problem begins. They do also not like heat. Temperatures above 30C will see the foliage wilting fairly quickly. So plant as early as possible, late to mid winter. And then provide some protection from the heat of summer. A little shade cloth will do the trick.
They can be grown in the garden or in large containers, a humus rich fertile soil is best and planting time is spring. In subtropical areas, plant them at the start of the wet season for best results.
- Plant them in spring in a well dug humus rich soil.
- Good drainage is essential
- Oca is planted at 5-7 cm deep and can be treated much like potatoes.
- Tubers will mature in about 4 months.
- Some gardeners like to ‘hill up’ as the plants grow
- Harvest Oca once the foliage begins to die back in autumn
After harvest you can store the tubers in a cool dry position until the next planting season.
Oca can be roasted, boiled and mashed or fried. It can also be eaten raw with some dressing. Tubers are sweeter if allowed to ripen in the sun for a few days. Try roasted them with roast lamb or beef.
Oca the New Zealand Yam – Tubers are available for sale from the following nurseries
Medicinal, Teas and Kitchen Herbs. Edible plants, scented and ornamentals.
Wide range of perennial edibles and medicinals, berries, fruit and unusual food plants, by mail order.