When to plant Carrot in Temperate Australia

Temperate zone — applies to Sydney, Melbourne, Adelaide, Perth, Newcastle and similar areas. Growing elsewhere? Cool · Subtropical · Tropical · Arid.

Carrots are sown direct from September through to May in temperate Australia — they hate transplanting, so the seed goes straight where the roots will grow. Sow just 4 mm deep, thin seedlings to 3–8 cm apart, and be patient: germination takes 10–20 days and the roots need 70–120 days to size up. What carrots want is deep, loose, stone-free soil that has not been recently manured, and a seed bed kept consistently damp for those slow first weeks. Get the germination right and carrots are one of the least demanding crops in the garden.

Sowing calendar — temperate zone

Green months are your sowing window: September to May.

Growing notes

Being half hardy, carrots handle the shoulder seasons well in temperate Australia. Autumn sowings from March to May will grow steadily through cool weather and shrug off light frosts, while spring sowings from September onward mature into summer. The gap in the calendar is winter sowing — soil below about 8°C sends germination from slow to hopeless — and the trade-off at the other end is that midsummer seed beds dry out in hours rather than days.

Soil preparation decides the crop. Dig deeply, break up clods, remove stones, and never sow into freshly manured ground; both obstacles and rich fresh nitrogen cause forked, hairy or stunted roots. A bed manured for a previous crop is ideal. Sow thinly along rows 25–30 cm apart, then thin ruthlessly — crowded carrots stay pencil-thin no matter how long you wait.

The number one failure is seed drying out before it germinates. Over 10–20 days a 4 mm covering of soil gives no buffer at all, so:

• Water the row gently every day in warm weather
• Lay a plank or damp hessian over the row and lift it at first emergence
• Sow into a fine, crumbly surface, not crusted clay
• Mark the row, because three weeks is long enough to forget where it is

Carrot at a glance

Companion planting

Grows well with

Tomatoes: Loosen soil around tomato roots

Chives: Deters carrot fly with strong scent

Leeks: Classic pairing — carrot fly repelled by leek, leek fly repelled by carrot

Keep away from

Dill: Cross-pollinate and hybridise if both allowed to flower; mature dill stunts carrot growth

Dill: Dill and carrot cross-pollinate; mature dill stunts carrot growth

Common questions

When can I plant carrots in temperate Australia?

Sow direct from September through to May — essentially any time outside winter. Autumn and spring sowings are the easiest to manage because the seed bed stays moist without daily attention.

How long do carrots take to grow?

Allow 10–20 days for germination and 70–120 days to harvest. You can start pulling baby carrots early, and roots left in the ground hold well in cool weather.

Why are my carrots forked and twisted?

Forking is almost always caused by stones, hard clods or fresh manure in the bed. Grow them in deep, loose soil that was manured for a previous crop, and thin seedlings so roots are not fighting each other.

Why didn't my carrot seed come up?

Carrot seed is sown only 4 mm deep and takes 10–20 days to germinate, so the usual culprit is the surface drying out at some point in that window. Keep the row damp every day, or cover it with a board until seedlings appear.

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