Lemongrass: Tropical Flavour, Tough as Nails

If you love Thai curries, Vietnamese pho, or just the clean, citrusy scent of lemongrass in your garden, here is the good news: this tropical herb is ridiculously easy to grow in most parts of Australia. Even better, you can start your very own patch from a bunch of supermarket lemongrass. Yes, seriously.

Quick Facts

The Supermarket Stalk Trick

This is one of those garden hacks that feels almost like cheating. Here is how to grow lemongrass from a $3 bunch of supermarket stalks:

1. Choose fresh stalks that still have the base intact (the bulb-like bottom part). Avoid any that look dried out or trimmed too short.
2. Peel off any dry outer layers.
3. Pop the stalks in a glass of water, base down, on a sunny windowsill.
4. Change the water every couple of days.
5. Within one to two weeks, you should see roots emerging from the base and new green growth from the top.
6. Once the roots are a few centimetres long, plant them out into a pot or garden bed.

That is it. From a bunch of cooking herbs to a thriving plant. It works almost every time.

Growing Conditions

Lemongrass is a tropical grass, so it loves heat, sunshine, and moisture. In northern Australia, it grows like a weed year round. In temperate and cooler areas, it grows vigorously through spring and summer and then goes dormant (or dies back) when the cold arrives.

Sun: Full sun is essential. Lemongrass wants as much warmth and light as you can give it.

Soil: Rich, well-drained soil with plenty of organic matter. Lemongrass is a hungry plant and benefits from regular feeding with a balanced organic fertiliser or compost.

Water: Moderate and regular watering, especially during hot weather. Lemongrass likes consistent moisture but will not tolerate waterlogged soil.

Spacing: Give lemongrass plenty of room. A single plant can grow into a clump up to a metre wide and over a metre tall. Space plants at least 60 centimetres apart.

Frost and Cold Weather

Lemongrass is frost tender. A hard frost will kill the leaves and can damage the crown of the plant. However, in many parts of Australia, it is tougher than you might expect.

In mild frost areas (Sydney, Perth, coastal regions), lemongrass will usually survive winter if you cut back the dead foliage and mulch heavily around the base to insulate the roots. It will come back from the roots in spring.

In cold areas (Canberra, Melbourne’s outer suburbs, Tasmania), grow lemongrass in a large pot and move it to a sheltered spot over winter. A sunny verandah, greenhouse, or even a well-lit garage can keep it ticking over until the warmth returns.

Container Growing

Lemongrass grows surprisingly well in pots, but you need a big one. Choose a pot at least 40 centimetres in diameter and use a rich, free-draining potting mix. Feed regularly with liquid fertiliser through the growing season, as potted plants burn through nutrients quickly.

Container-grown lemongrass is perfect for balconies and patios. Place the pot in the sunniest spot you have and water regularly. The added benefit of container growing in cooler areas is that you can move the pot to a protected position over winter.

Harvesting Lemongrass

To harvest, grab a stalk near the base and pull it firmly away from the clump with a slight twisting motion. It should come away cleanly. Alternatively, use a sharp knife to cut the stalk at soil level.

The most flavourful part of the stalk is the bottom 10 to 15 centimetres, the pale, tender section closest to the root. The upper green parts are fibrous but can be used in teas or for infusing flavour into soups and curries (just remove them before serving).

Freshly harvested lemongrass stores well in the fridge for a couple of weeks, or you can freeze whole stalks for months. Frozen lemongrass retains its flavour beautifully.

Cooking with Lemongrass

Lemongrass is essential in Thai, Vietnamese, Malaysian, and Indonesian cooking. Here are some ways to use it:

• Tom yum soup: Bruise a few stalks and simmer them in the broth.
• Curry pastes: Finely slice the tender base and blend it into green or red curry paste.
• Stir-fries: Thinly slice the pale base and add it early in the cooking process.
• Lemongrass tea: Slice a stalk and steep it in boiling water for a refreshing, caffeine-free drink.
• Marinades: Blend with garlic, chilli, and fish sauce for a brilliant chicken or prawn marinade.

Mosquito Repellent Properties

Lemongrass contains citronella, the same compound used in mosquito-repellent candles and sprays. While having a lemongrass plant on your balcony will not create an impenetrable force field against mozzies, crushing the leaves and rubbing them on your skin does provide some short-term repellent effect.

Planting lemongrass near outdoor seating areas can also help, especially when the breeze carries the scent around.

Propagation by Division

Once your lemongrass clump is well established (usually after one full growing season), you can divide it to create new plants. In spring, use a sharp spade to cut a section from the outside of the clump, making sure each division has plenty of roots. Replant immediately and water well.

A healthy clump can provide many divisions, so you will have plenty to share with friends and neighbours.

The Bottom Line

Lemongrass is one of those plants that just makes you happy. It looks tropical, smells incredible, and turns your kitchen into a Southeast Asian flavour factory. The fact that you can grow it from a $3 bunch of supermarket stalks makes it even better. Give it sun, water, and a bit of room to spread, and you will have more lemongrass than you know what to do with.