How to Grow Elephant Garlic in Australia

Elephant garlic (Allium ampeloprasum) is a bulbing leek in the onion family, Amaryllidaceae, grown for heads of huge, mild cloves. It is sold in Australia as Russian garlic. It is not a true garlic, and it grows in warm, humid districts where true garlic struggles. The usual disappointment is a single round bulb instead of a head of cloves, and most of its causes are in the gardener's hands.

Three mistakes that matter

1. Planting the small cloves. Small cloves and the hard little bulblets around the base usually grow a round (one solid, undivided bulb) with no flower stalk. Plant the largest cloves where you want divided heads, and grow the small ones on separately.
2. Spacing it like true garlic. A head can reach 10 cm or more across, so the 10 to 15 cm used for true garlic crowds it. Give every clove 20 to 30 cm, and keep the bed weeded.
3. Planting late. Elephant garlic usually needs 6 to 8 months in the ground. Cloves planted in late winter or spring often finish as rounds, so plant in autumn and leave the whole cool season for growth.

When to plant

Plant cloves once the summer heat breaks and the soil starts to cool, with March to May the main window across most of Australia. Plant once a year: the crop occupies the bed from autumn to early summer.

In cool districts, cloves missed in autumn can go in during spring, but expect mostly rounds from them.

Site, soil and setup

Onion-family crops compete poorly, so start with a bed cleared of weeds, especially those with thick taproots.

Never plant into fresh manure. On sticky clay, gypsum helps only if the clay is dispersive, so test a few dry crumbs in rainwater first.

Container growing

A pot suits heavy clay or a small courtyard if it holds at least 35 L, which means about 45 cm or more across. That fits three cloves about 20 cm apart. Fill it with premium potting mix and blend in a controlled release fertiliser for containers at the label rate at planting. Elephant garlic is sold as a single type, so there are no compact varieties to choose between.

• Water: when the mix is dry at finger depth, never while it is still damp, because cloves in soggy mix rot.
• Feed: fish and seaweed blend at 25 mL per 9 L fortnightly once shoots show, stopping when the lower leaves start to brown.
• Position: full sun, and under cover through long wet spells as the bulbs ripen.

Planting Cloves

Every plant starts from a single clove set where it will grow. Due to quarantine restrictions and our shipping policy, we cannot send elephant garlic cloves to Tasmania or Western Australia.

Vernalisation

Vernalisation (a spell of cold that prompts a bulb to grow and divide) is optional for elephant garlic. It copes with warm climates better than most true garlic and does not wait for long days to start bulbing. If autumn stays warm, keep the cloves in the fridge for about a week before planting to nudge them into sprouting. Plant them straight from the fridge.

Choosing cloves

If you start with a whole head, break it apart on planting day and keep the papery skin on each clove.

The hard-shelled bulblets on the base of a head are worth keeping. In their first year they usually grow a round, and a replanted round often grows into a full head with several cloves.

Planting

• Set each clove pointed end up, with about 5 cm of soil over the tip.
• Space cloves 20 to 30 cm apart each way.
• Water in once, then hold off until shoots appear, usually in 2 to 6 weeks, unless the soil dries out.
• Mulch with straw or sugar cane mulch once shoots are up.

Care by growth stage

Weed control and steady moisture decide the size of the bulbs. Weeks count from an autumn planting and shift with the zone, so watch the plants rather than the calendar.

Snap off each scape while it is young, once it clears the leaves, so the plant sends its energy into the bulb. Heavy feeding while bulbs form can trigger secondary growth, so keep to the table.

Companion planting

Elephant garlic sits in the bed for most of a year, so quick, low crops can share the space early on.

Grows well with

• Lettuce and spinach, shallow-rooted greens that feed at a different depth and are picked before the bulbs need the room.
• Radish and beetroot, fast, low crops that fill the gaps along the rows.
• Kale, which grows upward and takes little ground over winter.

Keep apart

• Onions, true garlic, leeks and chives, which share onion thrips, onion rust and white rot (Stromatinia cepivora).
• Broad beans, climbing peas and other tall winter crops on the north side, which shade the bed.

Harvesting Bulbs

Lift the bulbs when the tops turn pale green or yellow and some lower leaves have died, sooner in the tropics, later in cold districts.

• Dig one test bulb first: clove ridges should show clearly under the skin.
• Do not wait for every leaf to die, since heads left too long start to split.
• Loosen the soil with a fork and lift each bulb from underneath rather than pulling the stem.
• Brush off the soil, but do not wash the bulbs or break them apart.
• Keep plants that formed only a round: replant them in autumn, or eat them like a clove.

Curing

Curing (drying the bulbs so the skins and necks seal) is what lets elephant garlic store. Cure with the stems and leaves still on.

Store the heads in a dark, dry, airy place, not the fridge, where cool, damp air makes them sprout. Well-cured bulbs keep for up to 8 to 10 months, and for less in humid climates. Set the biggest, firmest heads aside as planting stock and keep them apart, around 10°C, until autumn.

Roast whole heads until soft, slice the raw cloves into salads, or cook them like onion in soups and stews.

Common problems

Rounds instead of heads. Small cloves, late planting and water or feed stress can all give single rounds. Replant them in autumn at full spacing, and see Three mistakes that matter.

Small bulbs. Weeds, shade, poor drainage and scapes left on all hold bulbs back; clear weeds early and snap scapes young. Read more

Rotting cloves. Waterlogged soil, or watering damp soil before shoots show, rots cloves in the ground; raise the bed on heavy clay. Read more

Split heads. Bulbs left in the ground after the leaves die back split open and store poorly, so eat those first.

Sprouting in storage. Garlic sprouts fastest between about 4°C and 16°C, which is why cool, damp storage sets it growing.

Pests and diseases

Most troubles arrive on planting stock or build up in beds that grow onion-family crops too often.

Onion thrips (Thrips tabaci). Tiny insects, common on garlic and onions in Australia, that feed in the leaf folds and leave leaves silvery. They thrive in hot, dry weather, so keep plants watered through dry spells. Read more

Onion rust (Puccinia allii). Bright orange or dark brown pustules erupt along the leaves in cool, damp weather, and heavy infections shrink the bulbs. It is a declared pest in Western Australia, so report any rust on onion-family plants there.

White rot (Stromatinia cepivora). Leaves yellow and wilt as white fluffy growth and black specks the size of poppy seeds coat the bulb base. The specks survive in soil for 15 years or more. Bag and bin affected plants, never compost them, and grow onion-family crops elsewhere.

Prevention first

• Plant clean cloves from a garden supplier, never garlic bought for eating, which can carry onion rust.
• Keep to the onion-family rotation set out in Site, soil and setup.
• Water the soil, not the leaves, since rust needs hours of wet foliage to infect.
• Pull self-sown onion-family plants and clean soil off tools and boots after working an infected bed. Read more

Tips

1. Leave one scape to flower as a harvest timer. When its head starts to dry, the bulbs are close to ready, though that plant's own bulb finishes smaller.
2. Grow a few plants for their flower heads, where stalks up to 2 m tall will not shade other crops. The mauve globes dry well for vases.
3. Slice the young leaves into salads like spring onion, and cook young scapes in stir-fries.
4. Keep any clump left unharvested inside one bed, because elephant garlic naturalises and, left to spread, can become a weed.