Most commonly recognised as sweet, pink-red tubers that are small, often about the size of a thumb and have a slightly shiny and ribbed surface. Sweeter, slightly smaller varieties, coloured yellow, apricot and golden are also now available in New Zealand.
New Zealand yams are different from the tropical yams grown in other cultures. In America, and therefore in American recipe books, the vegetables known as ‘yams’ are in fact sweet potatoes similar to Beauregard kūmara.
Yams grown in New Zealand originate from the South American Andes where they are known as Oca (Oxalis tuberosa). They made their way to New Zealand around 1860. Interestingly, it was not until the 1980s that Oca was first grown on a commercial scale and thus introduced to North Islanders who had been missing out on this seasonal winter speciality.
There is no need to peel yams, a quick scrub will suffice. Often baked, they are delicious with a drizzle of honey, maple syrup and a squeeze of citrus. Yams can also be boiled for mash, or thinly sliced to sauté or stir-fry. The natural sweetness is enhanced with flavours like ginger, orange, or sweet and sour sauces. Try yams sliced or grated raw into winter salads to add some texture to your dish.
Yams make an ideal staple on winter menus which comes as no surprise with the many comforting ways they can be prepared, which matches up with their seasonal availability from April through to October.
Yams are one of the highest vegetable sources of carbohydrate, so stay clear if creating any ketogenic friendly dishes.
Red Yams (Uwhiuwhi) – These are the yam variety Kiwis are most familiar with and are the most widely available. With red skins and light yellow flesh, when cooked their flesh becomes soft.
Ulluco or Earth Gems – Only available in New Zealand since 2003 and marketed as Earth Gems, these brightly coloured tubers range from yellow to magenta, pink, and even candy striped. They are very small in size, about 2–3 cm in diameter. The white to lemon-yellow flesh has a smooth, silky texture with a nutty taste, similar to beetroot. Their crisp texture remains even when cooked, along with their colour, making them an attractive ingredient to include for dish appeal.
Other sweeter, slightly smaller varieties, coloured yellow, apricot and golden are available from time to time.
Store at 0–2°C with a relative humidity of 90–100%, preferably in a dark spot.
The majority of the local crop comes out of the Manawatu and Canterbury regions.