When to plant Garlic in Subtropical Australia

Subtropical zone — applies to Brisbane, Gold Coast, Sunshine Coast, Coffs Harbour, Lismore and similar areas. Growing elsewhere? Temperate · Cool · Tropical · Arid.

Garlic is planted from April to July in the subtropical zone: break a bulb into cloves and sow them direct, pointy end up, 20–30 mm deep and 10–12 cm apart. Shoots appear in 14–21 days and bulbs need around 140 days, so an April planting in Brisbane is lifted around September, ahead of the humid storm build-up. Be honest about the odds, though — the subtropics are marginal garlic country, because bulbing is triggered by winter cold. Choose early or subtropical-adapted varieties, turban types especially, rather than long-storage cold-climate garlic, and plant your fattest cloves; small cloves make small bulbs.

Sowing calendar — subtropical zone

Green months are your sowing window: April to July.

Growing notes

Garlic is fully hardy, which makes it one of the few crops that could not care less about a subtropical winter — light frosts in the Lismore hinterland won't touch it. The threats sit at either end of the season instead. Plant too late, in July, and mild-winter districts may not bank enough cold for cloves to divide properly, leaving single round bulbs; harvest too late and spring humidity arrives before the crop can cure. April and May plantings get the longest cool run and consistently grow the best bulbs around Brisbane and the Sunshine Coast.

Give garlic full sun and a raised, free-draining bed — cloves sitting in soggy winter soil simply rot. Keep water steady while leaves are actively growing, then taper right off in the final month as bulbs mature; wet soil at that stage invites rot and splits the papery wrappers.

The region's signature failure is rust: orange-brown pustules spreading across the leaves during humid spells, usually late winter into spring. There is no practical cure once it establishes, so act early — keep full spacing, remove the worst-affected leaves, and never water overhead. If rust takes hold close to maturity, harvest immediately; bulbs that have already sized up are perfectly usable, they just won't store as long.

Garlic at a glance

Companion planting

Grows well with

Rosemary: Both deter pests; garlic deters aphids, rosemary carrot fly

Tomatoes: Deters spider mites and aphids on tomatoes

Strawberries: Deters aphids and fungal disease

Keep away from

Bean (Bush): Alliums stunt legume growth by inhibiting nitrogen-fixing bacteria

Bean (Climbing): Alliums stunt legume growth

Peas: Alliums inhibit nitrogen-fixing bacteria in legume roots

Common questions

When should I plant garlic in Brisbane?

Plant cloves from April to July, with April and May giving the best results. Bulbs take around 140 days, so an autumn planting is harvested in late winter or early spring.

Why didn't my garlic form a proper bulb?

Usually not enough winter cold — either a cold-climate variety unsuited to the subtropics or a planting made too late in the season. Use turban or other subtropical-adapted types and plant in April or May.

Can I plant supermarket garlic in the subtropics?

It's a gamble — much of it is imported, sometimes treated to prevent sprouting, and rarely a variety suited to mild winters. Buy seed garlic of an early or subtropical-adapted variety instead.

When is garlic ready to harvest?

Around 140 days from planting, when the lower leaves have browned but a few upper leaves are still green. In the subtropics aim to have it lifted and curing before the humid storm season.

Keep exploring