Oxalis tuberosa
Oxalidaceae
Oca, New Zealand Yam
Oca originates from the Andes in South America but is extensively commercially grown in New Zealand hence its common name.
It is a compact, bushy perennial plant 20-30cm tall with clover-like leaves.
Oca is a knobby root vegetable similar to artichoke but longer and more carrot shaped in its appearance, with cream to pale orange crisp flesh.
Uses
Oca may be boiled, fried or baked just like potatoes. It is also sometimes pickled or even eaten raw.
They have a tangy nutty, lemony taste when cooked it can also be eaten raw.
Culture
Oca is a very adaptable species that grows well in a range of climatic conditions from cold through to warm but not in sub-tropical or tropical areas over summer (temperature over 28°C causes wilting).
Frost will damage and even kill the foliage but not the tubers which will re-sprout. It tolerates a wide range of soil types.
Plant Oca in spring in cool areas, and to coincide with the wet season in sub-tropical or tropical regions.
Tubers should be covered with around 5cm of soil with plants spaced 30cm either way. Like potatoes, oca plants should have soil heaped around the base as they grow as this encourages tuber formation.
Cultivars
No information available at this time...
Plant Health
Few problems.
More info
Tubers start to form around 16 weeks after planting with harvests commencing at 26 weeks when the foliage dies back. Place the tubers in the sun for a few days if possible after harvest as this sweetens them. Oca do not keep as well as potatoes – take care not to bruise them when handling during and after harvest. Store at room temperature and in a dark place; can be stored, with care, for several months.