How to grow Lemongrass in New Zealand
Lemongrass is a clumping, subtropical grass grown for its lemon-scented stalks, essential in Thai and other Southeast Asian cooking, and for its leaves, which make a refreshing tea. It thrives in the warm, frost-free north, where a clump keeps growing for years. Further south frost kills it, so grow it in a pot that can come under cover for winter.
📖 Our full guide: How to Grow Lemongrass in New Zealand
At a glance
When to sow by region
| Region | When to sow | Regional note |
|---|---|---|
| Northland | October to February | |
| Auckland | October to February | |
| Waikato & Bay of Plenty | October to February | |
| Central North Island | November and December | Frost kills it. Plant after the frosts in a pot you can move under cover for winter. |
| Wellington & Lower North Island | October to February | |
| Nelson & Marlborough | November to January | Frost kills it inland. Plant Nov to Jan in a warm sheltered spot or a pot you can move under cover for winter. |
| Canterbury | November and December | Frost kills it. Plant after the frosts in a pot you can move under cover for winter. |
| Otago & Southland | November and December | Frost kills it. Plant after the frosts in a pot you can move under cover for winter. |
| Central Otago | November to January | Frost kills it. Plant after the frosts in a pot you can move under cover for winter. |
Where to plant
Lemongrass likes full sun, warmth and plenty of water in free-draining, fertile soil. It tolerates wind and salt, which makes it useful in coastal gardens. It grows best with summer heat and humidity, and slows right down or dies back in cold weather.
In frost-free gardens a clump stays evergreen. Where frosts occur, it goes dormant or dies, so a pot that can be moved under cover over winter is the safest way to keep it.
- Northland and Auckland: plant from October to February. Clumps stay evergreen in frost-free spots.
- Waikato and Bay of Plenty and Wellington: plant from October to January in a warm, sheltered spot; protect from frost or grow it in a pot.
- Nelson and Marlborough: frost kills it inland. Plant from November to January in a warm, sheltered spot or a pot you can move under cover for winter.
- Central North Island, Canterbury, Otago and Southland, and Central Otago: frost kills it. Plant after the frosts in a pot you can move under cover for winter.
How to plant
- The easiest way to start is with a plant from a garden centre, or a fresh supermarket stalk with the base intact. Stand the stalk in a glass of water on a warm windowsill until roots form, then pot it up or plant it out.
- From seed, sow clumps of two or three seeds about 5 mm deep in warm weather. Seed germinates in about 10 to 14 days.
- Plant into soil enriched with compost or blood and bone, about 30 cm apart for small clumps or up to 80 cm for big ones.
- Water in well and keep the soil moist while the clump establishes.
Watering and feeding
Water regularly through the warm months; lemongrass likes plenty of water as long as the soil drains. Keep it drier in winter when growth stops.
Feed every week or two through spring and summer with a liquid plant food or a general fertiliser, especially in pots, to keep the stalks tender.
Pruning and care through the year
- Trim old, brown leaves after frosts have passed in spring to tidy the clump and let new growth through.
- Divide large clumps in spring: dig up the clump, split it into sections with roots and replant.
- Wear gloves when handling the leaves, which have sharp edges.
Harvesting
Harvest through summer and autumn once the clump is established. Twist and pull or cut outer stalks at soil level, leaving the inner stalks to keep the plant growing. Use the tender white lower part of the stalk in cooking.
The leafy tops are good for tea or stock and can be dried. Whole stalks freeze well.
Growing in pots
Lemongrass grows well in a pot at least 30 cm wide and deep in quality potting mix, in a sunny, sheltered spot. Water and feed regularly in summer. In cold districts move it into a glasshouse, conservatory or sunny room for winter and water sparingly until spring.
Varieties
- Lemongrass (Cymbopogon citratus)
Pests and diseases
Lemongrass is rarely troubled by pests in New Zealand. Cold is its main enemy.
Lemongrass is rarely troubled by pests.
Diseases to watch for
- Rust Orange to brown streaks and pustules on the leaves in humid weather. Remove affected leaves and keep the clump open.
Common questions
Can I grow lemongrass from a supermarket stalk?
Yes. Choose a fresh stalk with the base intact, stand it in a glass of water in a warm, bright spot until roots form, then pot it up.
Will lemongrass survive winter?
In frost-free northern gardens, yes, and it stays evergreen. Where frosts occur it dies back or dies, so grow it in a pot that can come under cover for winter.
Which part of lemongrass do you eat?
The tender white lower part of the stalk, sliced finely or bruised and added to curries, soups and stir-fries. The leaves are used for tea and stock.
How do I harvest lemongrass without killing it?
Take the outer stalks, twisting or cutting them at soil level, and leave the inner stalks to keep the clump growing.
How big does lemongrass grow?
A clump grows about 1 to 1.5 m tall and spreads steadily. Divide it in spring when it gets too big.
Sources we checked: Yates NZ: How to grow lemongrass; Incredible Edibles: Lemongrass.