When to Plant Potatoes in NZ: Growing Potatoes by Region

Updated October 2026

Plant certified seed potatoes rather than supermarket ones. Mound soil up the stems as they grow to stop the tubers greening, and harvest once the tops die back. Watch for tomato/potato psyllid, the main NZ potato pest, and protect early plantings with fine mesh.

What it looks like as it grows

🌱 Plant profile: Potato, with sowing times for your region, companion plants and common pests.

When to Plant Potatoes in Your Region

Timing is everything in New Zealand, where the warm north and the cooler south are weeks apart.

Potatoes are planted as seed potatoes, from late winter in the north and from spring further south. These are the planting months for every region from our planting data. Each region links to its vegetable planting calendar, and the Potato plant page has spacing, companions and care notes for your region.

In Northland, Auckland, Waikato and the Bay of Plenty, Wellington and the lower North Island, and Nelson and Marlborough, seed potatoes go in from August to October. The central North Island plants in October and November, from mid October, because frost burns the young shoots. Canterbury plants from September to January, and Otago, Southland and Central Otago from October to January; the cooler southern summers let those regions keep planting into January as long as the crop gets steady water. Wherever frosts run into October or November, earth up or cover the shoots if a late frost is forecast. Our frost dates page has the average last frost for each region.

Best potato varieties for NZ

• Jersey Benne, Classic early waxy potato, great for salads and boiling; plant first. (Tui, Mitre 10, garden centres (seed potatoes, late winter))
• Rua, All-purpose maincrop with white flesh; dependable heavy cropper. (Tui, Mitre 10, garden centres)
• Agria, Yellow-fleshed maincrop, brilliant for mash, roasting and chips. (Tui, Mitre 10, garden centres)
• Ilam Hardy, Early all-purpose floury potato with white flesh. (Tui, garden centres)

How to grow potato

• Space plants about 30cm apart.
• Plant seed potatoes around 10cm deep.
• Position: full sun.
• Ready to harvest in roughly 90 days.
• Shoots appear in about 14 days.

Planting Seed Potatoes

Potatoes are grown from seed potatoes, small tubers grown for planting, rather than from true seed. Buy certified seed potatoes, which garden centres stock from late winter, and plant an early variety such as Jersey Benne first, followed by a maincrop such as Rua or Agria.

1. Choose a spot in full sun with loose, slightly acidic soil that drains well. Dig in compost, but avoid fresh manure and high-nitrogen fertiliser, which favour leaf over tubers.
2. Cut large seed potatoes into pieces with a couple of eyes each, and let the cut surfaces dry before planting.
3. Plant them about 10 cm deep and 30 cm apart, with the sprouts facing up.
4. Feed a balanced fertiliser at planting time and water in.
5. As the stems grow, hill soil up around them to keep the developing tubers covered and away from light.
6. Water steadily once tubers form, give a potassium feed as they swell, and ease off as the foliage dies back.

Hilling, also called earthing up, is the step that matters most. Tubers exposed to light turn green, and green parts should not be eaten. In the colder regions, a mound of soil over the young shoots also protects them from a late frost.

Growing Potatoes in Bags and Pots

Potatoes grow well in a container, which suits small gardens, decks and courtyards. Our plant data calls for a container at least 50 cm deep, and a hessian bag or a purpose-made potato bag works well. Put a layer of potting mix in the bottom, sit the seed potatoes on it with the sprouts facing up, and cover them. As the stems grow, keep adding mix around them, which does the same job as hilling in the garden.

Bags dry out faster than beds, so water steadily once the tubers start forming, because uneven watering gives knobbly and split potatoes. Feed as you would in the garden, with a balanced fertiliser at planting and a potassium feed as the tubers form. When the tops die back, tip the bag out and collect the crop. Our potatoes in containers guide has more on bag sizes and how many seed potatoes to plant in each.

How Long Do Potatoes Take to Grow?

Our plant data allows about 90 days from planting to harvest, roughly three months, with the first shoots through in about 14 days. New potatoes come earlier, because they are ready to dig once the plants flower. The main crop is left in the ground until the tops yellow and die back.

Planting potatoes for Christmas

If you want new potatoes at Christmas, count back about 90 days from the day: seed potatoes planted in late September are due around Christmas, and because new potatoes can be dug once the plants flower, a planting in August or early September gives you some leeway. Jersey Benne, the early waxy potato in our variety list, is the one to plant first. That timing works in every region that plants in September or earlier. In the central North Island, Otago, Southland and Central Otago, planting starts in October, so on the 90 day figure the first new potatoes are more likely in January.

When and How to Harvest Potatoes

Dig new potatoes once the plants flower. For the main crop, wait until the tops yellow and die back. Loosen the soil with a garden fork and lift the tubers, working out from the stem so you find them all. Our plant data expects about 1 to 2 kg of tubers from each plant.

Store potatoes in a cool, dark, dry place, where they keep for up to 2 months. Do not refrigerate them, and keep them away from light, which turns the skins green.

Companion planting

Grow potato near: Beans, Nasturtium, Marigold, Corn.

Keep potatoes away from tomatoes, capsicum, eggplant, pumpkin and cucumber, which our companion data lists as poor neighbours. Tomatoes and potatoes share the tomato/potato psyllid and both blights, which our tomato and potato blight guide explains.

Pests and problems

Watch for: Tomato/potato psyllid, Aphids. See our NZ pest and disease guide for organic control.

When it goes wrong

The most common ways potato trips people up, and what to change next time:

Green patches on the tubers

Exposed to light. Mound soil over the developing tubers and store them in the dark. Do not eat green parts.

Leaves brown and collapse in wet weather

Late blight. Remove affected tops, improve airflow, and harvest before it spreads to the tubers.

Lots of leaf, few potatoes

Too much nitrogen. Ease off rich feed and make sure they get full sun.