New Zealand Yams Cultural Notes - NewGipps Vegetable Flower Herb seeds and Bulbs

Help and Information



Also known as OCA (Oxalis tuberosa) these tasty and attractive small tubers are not to be confused with the Oxalis of weed fame. This useful tuber bearing plant has been grown in the Andes Mountains for centuries as an important source of food.

Closer to home, it is widely cultivated in New Zealand home gardens, and was once an important crop in Europe. In years past a range of different coloured tubers were available, but at the present it is mainly the pink variety that is available. The tuber are small, with shallow eyes. They are formed late in their growing period (around April/May), from tubers planted the previous Spring.


Depth - 10 cm.

Spacing - Rows - 40 cm

Between Rows - 60 cm.


Plant in Spring when all danger of frost is past. Tubers will not begin to grow until the soil has warmed sufficiently. Prior to planting, store the tubers in a well ventilated open position.


Prior to planting apply a complete fertiliser, preferably one with a high phosphorous content, using 120 to 150 grams/sq.m. Avoid heavy use of fresh manures and composts.


Hill the soil around the base of the plants, avoiding deep cultivation that may damage the shallow root system. Keep well watered during dry periods and ensure weeds are kept under control.


Maturity appears to be affected by day length and rarely do tubers form (in southern areas) before the April/May period no matter when the tubers were originally planted. It appears that the longer the growing season, the better the yield and size of the tubers will be. Good tubers will be 8 to 12 cm long and 2 to 3 cm across, although many smaller specimens can be expected.


Dig the tubers once fully formed. This is usually by mid May.


Tubers MUST be exposed to light for around 2 weeks after digging before being eaten to allow for the breakdown of acids in the tubers. If eaten too soon the taste can be extremely unpleasant. Tubers can be roasted or baked.