When to plant potatoes in Sydney NSW

How to give your spuds the best chance for success.

It’s best to decide on your planting date before you actually go out and get your seed potatoes.

In this post, we discuss when to plant potatoes in Sydney, harvesting tips and other growing information.

When to plant potatoes in Sydney

In theory, potatoes can be planted at any time of the year in Sydney. However, keep the following in mind:

  • Potatoes are a cool season crop so Jan – Feb in Sydney is often too hot
  • Potatoes need 60-90 days of frost-free conditions

Therefore, the best time to plant potatoes in Sydney is early spring, just before the last expected frost. If you’re not at risk from frost, you can generally plant them year-round.

In the northern parts of NSW (or in QLD), March and April are among the best times for planting potatoes, when the soil is warm but extreme heat is less common. This time of the year is also better in terms of pest problems.

Potatoes grow best in soil temperatures between 10°C and 30°C. They’ll do best if planted in fertile well-drained soil.

Can you grow potatoes in Sydney winter?

Potatoes require frost-free conditions to grow healthy and strong.

In Sydney’s west, frost is a frequent occurrence in winter. However, in the city centre, it’s much less common, occurring only once or twice a year.

If you get frost in your area, planting times should avoid June or July, as these are the coldest months.

The best soil for growing potatoes

Your soil should drain well and be loose, with a pH level between 5.5 and 6.5, though you can amend it by adding lime or sulfur as needed.

You can test the pH of your soil with a soil testing kit from your local gardening centre.

Before planting, you can enrich your soil with compost, which will add nutrients and help it retain moisture.

What are seed potatoes?

Potatoes are usually grown from seed potatoes. A seed potato is a potato that has been prepared to be planted so that it will grow into a new potato plant.

Seed potatoes are stored tubers of the previous year’s crop. They can be purchased in the correct planting season for each area (check with a local garden centre for advice on when this is).

How to plant seed potatoes

  • Expose the seed potatoes to sunlight until they start to grow shoots
  • Prepare the soil
  • Dig a trench about 15cm deep
  • Plant seed potatoes with a spacing of 30 – 40 cm between each one (shoots facing upwards)
  • Backfill the trench with soil
  • Mound up some of the earth from either side to make it higher than the rest of your garden bed. This creates drainage for heavy rains.
  • Water well
  • Cover the shoot with soil when they appear

Potato pest control

Pests that you may encounter with your potato crop include:

  • Potato tuber moth (PTM)
  • Tomato potato psyllid (TPP)
  • Helicoverpa armigera
  • Green peach aphid (Myzus persicae)
  • Potato aphid (Macrosiphum euphorbiae)
  • Onion thrips
  • Tomato thrips
  • Western flower thrips
  • African black beetle
  • Cluster caterpillar
  • Bacterial wilt

To prevent pests, attract beneficial insects to your garden by building a garden that promotes biodiversity. Mulch the soil heavily with straw and practice crop rotation.

If you think you have a pest infestation, try to identify the pest before taking measures to treat the problem.

Fertilising potatoes

Potatoes are heavy feeders and require plenty of nutrients as they grow. Fertilise your potatoes a couple of weeks after planting them.

Use an all-purpose fertiliser that isn’t too high in nitrogen.

Watering potatoes

Potatoes thrive when they have consistent access to water. They grow the best when their soil is kept evenly moist, with the soil never fully drying out.

Aim for around 5 – 8cm of water per week and retain at least 20 cm of moist soil underground.

When to harvest potatoes in Sydney

After a few months, it’ll be time to harvest your potatoes.

Harvest potatoes when the plants are brown and dying back. The tops of the vines should be completely dead and the leaves may be yellowing or browning. This usually means they are mature and ready for harvest.

Also, check they have a thick skin before harvesting. Potatoes need a thick skin to help prevent bruising during storage, and this generally happens as the plant dies back.

Determinate vs indeterminate potatoes

When you’re deciding which type of potato to plant, there is an important factor to consider: determinate vs indeterminate potatoes.

  • Determinate potatoes grow in one layer only. This means you don’t need to mound soil around them.
  • Indeterminate potatoes grow in multiple layers and it’s therefore important to mound soil around them.