Lemongrass

Cymbopogon citratus

Fragrant tropical grass whose citronella oils help see off mosquitoes.

Light Full sun
Water Moderate
Hardiness Tender
USDA zones 9a–11b
Height 1–1.5 m
Spread 23.6 in
Spacing 30–45 cm
Sow depth Shallow
To harvest 90 days
Per square 1 / sq ft

Spacing & sowing

Plant spacing
15.7 in
In-row spacing
13.8 in
Between rows
23.6 in
Square-foot density
1 per square

Calendar (from your frost dates)

Sow indoors
56 days before the last spring frost
Plant out
21 days after the last spring frost
First harvest
90 days after the last spring frost
Harvest ends
at the first fall frost

Growing

Type
Herb · Perennial
Botanical family
Mixed / other
Sunlight
Full sun
Watering
Moderate
Soil
Rich, moist, warm
Feeding
Gentle all-organic
USDA zones
9a–11b
Frost tolerant
No
Season
Warm Season
Harvest type
Continuous Harvest
Start from
seed

Growth stages

  • 0 d Sow seeds
  • 14 d Germination
  • 150 d Harvest

Harvest

When
Harvest stalks from mid–late summer onward, once individual stems have thickened to at least 1–1.5cm at the base — typically 4–6 months after planting. In the UK and cold US zones, harvest the whole crop in autumn before frost (or pot up divisions to overwinter indoors); leaves for tea can be trimmed any time in the season.
What to look for
Stem bases swollen, firm, and pale like miniature leeks, with a strong lemon burst when a leaf is crushed. Thin, pencil-like stems are worth leaving to fatten.
How to harvest
Grasp an outer stalk low down and twist-and-pull, or cut it at soil level with a knife, taking outer stalks first and leaving the clump's center growing. Trim off the leafy tops (save them for tea — the edges are razor-sharp, so wear gloves) and use the tender lower 10–15cm bulb end for cooking.
How often
Take a few stalks at a time from a healthy clump all season — each removal encourages the clump to tiller and thicken. A container plant overwintered frost-free will regrow and can be divided each spring for a bigger harvest every year.
Storing the crop
Whole stalks keep 2–3 weeks loosely wrapped in the fridge. Lemongrass freezes exceptionally well — freeze whole trimmed stalks or chopped pieces, usable straight from frozen — and the leaves dry well for tea. Stalks stood in water will even root, giving you next year's plants.

Garden allies

Beneficial predators that hunt this plant's pests — grow their favourite flowers nearby to recruit them. companion plant

  • Garden birds Passeriformes

    Both things are true: birds strip your currants and a brood of blue tits takes several thousand caterpillars out of one fruit tree in a fortnight. Net what you must and welcome them everywhere else — a nest box near the apples is worth more than a spray.

  • Aphid midge Aphidoletes aphidimyza
    Hunts Aphids

    A tiny midge whose orange maggots paralyze aphids and drink them dry, twenty or more each. Sold as a greenhouse biological control and resident outdoors wherever there are small nectar flowers and an unsprayed aphid colony to find.

  • Assassin bug Reduviidae
    Hunts Aphids

    A patient ambusher with a curved beak it drives into whatever it catches — caterpillars, beetles, bugs, and the occasional bee, so count it a generalist rather than a specialist. It will jab a careless finger too, so admire it and leave it be.

  • Beneficial nematodes Steinernema & Heterorhabditis spp.

    Microscopic worms watered onto damp soil that hunt down soil-dwelling grubs and release a bacterium that kills them within days. Timing is the whole thing: warm, damp soil and a small target grub, which means late summer for most of what they are used against.

  • Big-eyed bug Geocoris spp.
    Hunts Aphids

    A stubby 3 mm bug with enormous wrap-around eyes, working the soil surface and the low foliage for aphids, mites, thrips and insect eggs. It is the main natural check on chinch bugs in a lawn and it is killed outright by insecticide.

  • Centipedes Chilopoda

    Flat, fast, one pair of legs to a segment — and a predator, unlike the slow round millipede it is constantly confused with. It hunts slugs, cutworms, springtails and woodlice by night under mulch and stones. Learn the difference and leave this one alone.

  • Damsel bug Nabidae
    Hunts Aphids

    A slender, mantis-armed bug that grabs aphids, small caterpillars, and thrips in low crops and meadowy edges. Leave a strip of unmown grasses and flowers for it to overwinter in.

  • Dragonflies & damselflies Odonata
    Hunts Aphids

    Aerial hunters that take mosquitoes, midges and small flies on the wing all day, and whose larvae spend a year or more clearing the same insects from the water. A pond with planted margins and no fish is the way to have them.

  • Frogs & toads Anura

    A resident toad works the beds every night for slugs, cutworms, and weevils. Recruit them with water — even a sunken basin pond — plus damp shade and an upturned-pot toad house; skip the slug pellets that poison their prey.

  • Green lacewing Chrysoperla carnea
    Hunts Aphids

    Its bristly larvae — "aphid lions" — impale aphids, mealybugs, thrips, and mite colonies, eating hundreds a week. Adults feed on nectar and pollen from small open flowers and overwinter in hollow stems left standing.

  • Ground beetle Carabidae

    Fast, glossy night hunters that patrol the soil surface for slugs, cutworms, and root-fly larvae. Give them daytime cover — thick perennial edges, stepping stones, a log — and skip the tillage that wrecks their burrows.

    Plant nearby LavenderMintThyme
  • Hedgehog Erinaceus europaeus

    A European animal, and worth saying so plainly: there are no hedgehogs in North America, and the ally that does the same night shift here is the toad, the opossum or the ground beetle. Where they do occur, cut a gap in the fence and skip the pellets.

  • Hoverfly Syrphidae
    Hunts Aphids

    Bee-mimicking flies whose legless larvae graze aphid colonies clean while the adults pollinate. A ribbon of shallow, nectar-rich flowers kept in bloom all season recruits wave after wave of them.

  • Ladybird (lady beetle) Coccinellidae
    Hunts Aphids

    The gardener’s favorite ally: adults and their alligator-shaped larvae each eat thousands of aphids, plus scale, mealybugs, and other soft-bodied sap-suckers. Grow flat, open flowers for the adults and never spray a colony that ladybird larvae are already working.

  • Minute pirate bug Orius spp.
    Hunts Aphids

    A pinhead-sized true bug that is the best natural check on thrips, and happily spears aphids, mites, and insect eggs too. It needs pollen when prey is scarce, so keep something flowering nearby.

  • Parasitic wasps Braconidae & Trichogramma
    Hunts Aphids

    Tiny, stingless wasps that lay eggs in or on caterpillars, aphids, and moth eggs — the white cocoons riding a hornworm are their calling card, so leave that caterpillar be. Umbel flowers with shallow nectar keep the adults fuelled.

  • Praying mantis Mantidae
    Hunts Aphids

    A sit-and-wait ambusher that snatches caterpillars, beetles, and anything else that wanders close — friend and foe alike, so count it a mixed blessing. Tall, structured plantings give it perches and egg-case anchors.

  • Rove beetle Staphylinidae

    Slim, quick beetles with short wing cases that hunt in soil and litter, taking root-fly eggs and larvae, fungus-gnat larvae, and mites. Mulch and undisturbed ground keep them resident year-round.

    Plant nearby MintThyme
  • Salamanders & newts Caudata

    Damp-loving hunters of slugs, worms, woodlice and beetle larvae that spend the day under a log or a stone and work the beds at night. Companions to the toads: they want the same damp shade, the same log pile, and the same absence of slug pellets.

  • Snakes & lizards Colubridae & Phrynosomatidae

    A garter snake works the beds for slugs and voles and a fence lizard clears grasshoppers off a sunny wall. Almost every snake a gardener meets is harmless and useful; give them a log pile, a warm flat stone and a bit of cover and they stay.

  • Soldier beetle Cantharidae
    Hunts Aphids

    Soft-winged beetles seen mating on flower heads in high summer; adults and larvae both take aphids and soft grubs. Open composite flowers are their landing pads and hunting grounds.

  • Spiders Araneae
    Hunts Aphids

    Webs, ambushes, and night patrols make spiders the garden’s steadiest generalist predators, taking whatever flies or crawls past. Mulch, ground cover, and undisturbed corners keep the population dense.

    Plant nearby LavenderThyme

Germination & growth

Min soil temp
68 °F
Photoperiod
day neutral

Did you know?

The citronella oils that scent the stalks are also used in natural insect repellents.