Growing potatoes

The potato is the fourth largest food crop grown in the world – only wheat, maize and rice exceed its annual yield.

It was first grown as a food crop in Peru and Bolivia 8000 - 1000 years ago and left South America to Spain in 1560 and to the UK in 1580. Captain Cook introduced it to New Zealand on his second voyage in 1773 where it quickly became a staple food.

It’s very hard to beat the taste of new potatoes, freshly dug from the garden – I’m drooling at the thought!

And they are so easy to grow even if you do not have a vegetable garden. Early varieties are available now so you can expect wonderful waxy new potatoes in 3-4 months.

THE BASICS
Selection
You must use certified Seed Potatoes (from us of course) not the ones sprouting at the bottom of a cupboard; they can be prone to virus. Certified potatoes are more aggressive growers and a lot more resistant to disease.

You will then need to ‘sprout’ them before you plant. Do this by laying them out in a single layer in a box or seed tray in a warm, dry, airy spot (an egg carton is also suitable). “Eyes”, small buds, will appear in about 4-6 weeks. and when they have grown into shoots 3-4cm long they are ready to plant. Remove all but 3 of the strongest shoots.

Varieties
Roasting – Moonlight, Agria or Rua
Mashing – Moonlight, Agria and Illam Hardy
Boiling, new spuds – Nadine, Jersey Benny, Cliffs Kidney

SITE AND PLANTING

While waiting for the potatoes to sprout you can prepare the site. Choose a spot with full sun. It is important for the soil to be free draining, as they do not enjoy wet feet. Do not plant on ground that held potatoes of tomatoes the year before. If you are prone to frost do not plant until spring when the threat of frost is over.

Dig over and cultivate to about 20cm (a fork depth) and incorporate compost and Potato fertiliser at 100gms a square metre.

Dig a trench 10-15cm deep and place the seed potatoes 30cm apart (early varieties) or 40cm for main crop. Place with the shoots uppermost and cover with a low ridge of soil. Space rows 60cm apart.

As the shoots emerge through the soil, “earth up” -ie rake more soil up on to the ridge, covering all but a few centimetres of new leaves.

Repeat every three weeks until growth slows or when they start to flower. Potatoes turn green and poisonous when exposed to light. Water well in dry periods.

HARVESTING
The Potato will tell you when it is ready to be harvested – resist the urge to dig around the crop and take a peak!

Early varieties are ready when the flowers open, in 3 months after planting. Main crop and late season varieties should not be dug until the tops have completely died off.

GROW IN A BAG
If you only have a small garden or want to get them started before frosts are over, try this.

Fill a planting bag (PB40), bucket or pot one third full of compost and potting mix. Plant 2 or 3 potatoes in the bag, with their shoots pointing upwards. Cover with 5 cm of mix.

Place outside in a sunny frost-free position. When the green shoots are 15-30cm tall cover with more mix and repeat this until the container is full.

We use this method at the Garden Centre by growing them inside old car tyres, starting with 2 tyres and then adding tyres and soil as the potatoes grow.