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Onion

Allium cepa

Amaryllidaceae
Days to harvest: 100150 days
Spacing: 10 × 30 cm
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When to plant onion in Australia

Plant onion February to May in temperate climates (Melbourne, Adelaide, Sydney); January to March in cool climates (Canberra, Hobart, Ballarat); April to June in subtropical climates (Brisbane, Gold Coast); May to July in tropical climates (Darwin, Cairns); April to June in arid climates (Alice Springs, Mildura).

Can be grown from seed, seedlings, or sets (small bulbs — easiest). Harvest when foliage flops over and yellows. Cure in a dry airy spot for 2 weeks before storage.

Growing guide

Sunlight

4–6 hours direct sun per day

Watering

Low — drought tolerant once established

Spacing

10cm between plants, 30cm between rows

Frost tolerance

Hardy — tolerates frost

Frequently asked

How long does onion take to grow in Australia?
Onion takes 100–150 days from sowing to harvest, depending on variety and climate.
How much space does onion need?
Space onion 10cm apart in rows 30cm apart. Each plant needs 4–6 hours of sun per day.
Can I grow onion in Melbourne in winter?
Onion is generally not planted in Melbourne over winter. The temperate planting window is February to May.
What should I plant next to onion?
Companion plants for onion vary by garden conditions. Add onion to your patch in My Veggie Patch to see personalised companion recommendations.

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