It is quite confusing, as the vegetables we know as yams in New Zealand aren’t yams at all, according to the rest of the world.
They belong to a different plant family, but we call them yams anyway!
Our New Zealand yams are Oca (Oxalis tuberosa), originating from high altitudes in the Andes, in Peru.
The sweet tubers are small, often about the size of a thumb, are pinky-orange in colour and have a slightly shiny and ribbed surface.
Other sweeter, slightly smaller varieties, coloured yellow, apricot and golden are also available.
Growing yams
If you have always wanted to grow some yams, why not try it?
I always find that growing something new is the way to learn about various vegetables.
You will see yam seeds appearing in some garden centres around winter, usually when you see seed potatoes.
If you can’t find any yam seed, my suggestion is to pop down to the supermarket to find some good-looking, unblemished yams and plant these instead.
Make a start on sprouting your yams and plant them out when the risk of frost has passed (around October).
Put your seed yams in a seed tray or cardboard box in a nice dry place but away from where any rodents can get them, and leave the yams to sprout for a few weeks.
The yams are ready to plant when the sprouts are about 6cm long.
Planting yams
Make sure your vegetable plot is well dug over and give it a good feed of compost, blood and bone or even some sheep pellets.
You then need to prepare your furrows or mounds, spacing sprouted tubers about 45cm apart.
Plant at a depth of 10-12cm. Make sure you place the new sprouts facing upwards and water in well.
You will need to keep the tubers well-watered, and this will be dependent on your weather conditions.
When the weather warms up, to help your yam patch retain moisture, it would be a clever idea to mulch, using organic mulch such as pea or lucerne straw lightly.
Like potatoes, tubers can push up through the soil, so mounding them with extra soil might be needed.
The tubers put on most of their growth late in the season.
In cooler regions, harvest after the first or second frost, because the cold improves the flavour and sweetness.
You must dig up the tubers, making sure you do not leave any in the ground as they will sprout aggressively next year.
A good idea is to use a dedicated space for your yams or plant them in a large pot.
Yes, they can be a bit of an invasive thug if you just plant them anywhere.
Under supervision, they will add a mouthful of sweetness to your next roast, and you can steam them for a change.
Tubers can be stored in a cool, dry, well-aired place for a few months.
I store mine inside, away from prying eyes and cute whiskers, if you get my drift!
Why not try yams?
Oven-roasted, you will wonder why you haven’t tried them sooner, and the thing I love most about them is that you don’t need to peel them!