When to plant zucchini, pumpkins and cucumbers

The cucurbit family is frost-tender and needs warm soil to germinate. Sow too early and the seed sits in cold ground and germinates poorly; sow pumpkins too late in a cool climate and the fruit won't ripen before autumn.

Quick answer

Sow once the frosts are over and the soil has warmed to at least 15–16 °C: from September in temperate Australia and most of New Zealand, from October in cool areas and the New Zealand south. In the tropics, sow them in the dry season from April, and in the subtropics from August.

Zucchini crop within about 6–9 weeks of sowing and cucumbers within 7–12, so both can be sown until mid-summer. Pumpkins take 12–20 weeks: in cool climates sow them by December.

Planting months by climate zone

The charts come from the same data as the planting calendar. Tap a zone for its full calendar.

Zucchini

ZoneJFMAMJJASONDSow or plant
TropicalyesyesyesyesyesApr–Aug
SubtropicalyesyesyesyesyesyesyesAug–Feb
Arid and semi-aridyesyesyesyesyesyesyesSep–Mar
TemperateyesyesyesyesyesSep–Jan
CoolyesyesyesOct–Dec
NZ warm northyesyesyesyesyesyesSep–Feb
NZ temperateyesyesyesyesyesyesSep–Feb
NZ cool southyesyesyesyesyesOct–Feb

Pumpkin

ZoneJFMAMJJASONDSow or plant
TropicalyesyesyesyesApr–Jul
SubtropicalyesyesyesyesyesyesyesAug–Feb
Arid and semi-aridyesyesyesyesyesyesSep–Feb
TemperateyesyesyesyesSep–Dec
CoolyesyesyesOct–Dec
NZ warm northyesyesyesyesyesyesAug–Jan
NZ temperateyesyesyesyesSep–Dec
NZ cool southyesyesyesOct–Dec

Cucumber

ZoneJFMAMJJASONDSow or plant
TropicalyesyesyesyesyesApr–Aug
SubtropicalyesyesyesyesyesyesyesyesAug–Mar
Arid and semi-aridyesyesyesyesyesyesyesAug–Feb
TemperateyesyesyesyesyesyesSep–Feb
CoolyesyesyesyesOct–Jan
NZ warm northyesyesyesyesyesSep–Jan
NZ temperateyesyesyesyesyesSep–Jan
NZ cool southyesyesyesyesSep–Dec

sow or plantnot recommendedthis month

The first month of a window in a frosty zone is for sowing in pots under cover; plants go out once the frosts finish. When you pick your town in the planting calendar, it flags these crops in any month that still averages a frosty night or more there.

Soil temperature is the real signal

University extension services agree on the threshold. Purdue and Utah State say cucurbit seed needs soil of at least 60 °F, about 16 °C, and germinates poorly in anything cooler. Oklahoma State gives 60 °F at planting depth as the minimum for squash and pumpkins, with 70–90 °F, 21–32 °C, the best range. Utah State adds that germination is fastest at around 32–35 °C.

A cheap soil thermometer pushed in to seed depth in mid-morning takes the guesswork out. If you want an early start, sow in pots indoors: Yates suggests starting cucumbers 3–4 weeks ahead and zucchini 2–4 weeks ahead, then planting them out after the last frost.

Crop by crop

CropSpacingReady after sowingNotes
Zucchini70–100 cmAbout 6–9 weeksSow direct after the last frost
Cucumber30–60 cm, or up a trellisAbout 7–12 weeksSow direct in warm soil, or start in pots 3–4 weeks ahead
Pumpkin1–2 mAbout 12–20 weeksNeeds room to sprawl; sow by December in cool zones

The spacings and times are those in the planting calendar, taken from Australian seed company tables. The plant spacing calculator turns a spacing into a plant count for your bed. In a pot, University of Maryland Extension recommends at least 8–10 US gallons, about 30–38 litres, for cucumbers and winter squash such as pumpkins, and 4–6 gallons, 15–23 litres, for summer squash such as zucchini.

In the tropics and subtropics

In Darwin and the north, zucchini, pumpkins and cucumbers are dry-season crops, sown from April as the wet season ends. The subtropics can sow them from August through summer, with the heat and humidity of midsummer the hardest time. In the Top End, the NT Government recommends the dry season for most vegetables, and its Katherine office lists cucumber, zucchini and melons among the crops grown successfully there.

Questions

When should I plant zucchini in Australia?

From September to January in temperate areas, October to December in cool areas, August to February in the subtropics and April to August in the tropics. Sow once the soil is at least 15–16 °C and the frosts are over.

When is it too late to plant pumpkins?

In cool areas, after December: pumpkins take 12–20 weeks and need to ripen before the autumn frosts. In temperate areas the calendar's window closes in December too; in the subtropics sowings run to February.

How warm does the soil need to be for cucumber seeds?

At least about 16 °C (60 °F), according to Purdue and Utah State extension. They germinate fastest at around 32–35 °C.

When do you plant zucchini in New Zealand?

From September to February in the north and centre, planting seedlings out after the frosts, and from October in the cool south, where the Kings Seeds southern chart holds seed sowing back until November.

DueRiva, maker of GardenMathsThe planting months come from the site's planting calendar, compiled from Australian and New Zealand gardening authorities. Soil temperatures come from university extension services. Nothing here is sponsored. About GardenMaths.

Sources

  1. Purdue University Extension, HO-8: Growing cucumbers, melons, squash, pumpkins and gourds – minimum soil temperature.
  2. Utah State University Extension, Cucurbits: planting, spacing and thinning – germination temperatures.
  3. Oklahoma State University Extension, Squash and pumpkin production – minimum and best soil temperatures.
  4. University of Maryland Extension, Types of containers for growing vegetables – container sizes.
  5. Yates, how-to-grow guides and seed-packet climate guides – starting cucumbers and zucchini in pots.
  6. NT Department of Primary Industry, Fisheries and Mines, Katherine Rural Review no. 270 (April 2006): Home vegetable growing in the Katherine region.
  7. Planting months, spacing and harvest times: the GardenMaths planting calendar, from ABC Gardening Australia, the Diggers Club, Eden Seeds, the NT Government, Tui, Kings Seeds and others listed on each zone page.

Last reviewed 23 September 2026 · Report an error

What else goes in this month?

Pick your town and see every vegetable and herb to sow now, with frost warnings for tender crops.

Open the planting calendar