Lemon Grass: How to Grow, Care For, and Use It
Lemon grass (Cymbopogon citratus) is a tender tropical clumping herb that grows as a perennial only in USDA zones 8 to 11 and gets dug up or moved indoors everywhere colder. It is a culinary and ornamental plant, not a lawn turf, and the potted-plant-repels-mosquitoes claim is mostly a myth: the citral oil only works once you crush the leaves and apply it to skin. This guide covers what lemon grass needs, how to overwinter it where it cannot survive frost, when to harvest, and how it differs from the citronella plant people confuse it with.
What is lemon grass and is it a lawn grass?
Lemon grass is a tropical clumping herb in the Cymbopogon genus, grown for the lemon-flavored base of its stalks, not for ground cover. It forms a dense fountain-shaped clump 3 to 5 feet tall and roughly 3 feet wide, with blades about half an inch wide. You harvest and use it, you do not mow it. It belongs in a garden bed or a container, the same way you would site an ornamental grass.
The species used in cooking and tea is Cymbopogon citratus, sometimes called West Indian lemongrass. It is native to tropical Asia and prefers regular rainfall and humidity, which is why it grows slowly in spring and then explodes once summer heat arrives.
If you are looking for a true low-water replacement for a lawn, lemon grass is not it. Our guide to drought-tolerant lawn alternatives covers native grasses and ground covers built for that job. Lemon grass is a feature plant or a kitchen crop.
What growing zone does lemon grass need?
Lemon grass survives winter as a perennial only in USDA hardiness zones 8 and warmer, and reliably overwinters outdoors in zones 9 to 11. In zones 8a and below, gardeners treat it as an annual or dig it up and bring it inside before frost. It has no real cold tolerance: growth stalls below about 50 degrees Fahrenheit, and a hard freeze kills the top of the plant.
Check your zone against the 2023 USDA Plant Hardiness Zone Map at planthardiness.ars.usda.gov before deciding whether to plant in-ground or in a pot. The map was revised in November 2023 and shifted roughly half the country a half-zone warmer than the prior 2012 version, so an older zone label may be out of date.
| USDA zone | How to grow lemon grass | Winter plan |
|---|---|---|
| 9 to 11 | In-ground perennial, full sun | Survives outdoors; may brown at the tips in a cold snap |
| 8a to 8b | In-ground, mulch heavily | Risky outdoors; safer to dig and pot up |
| 6 to 7 | Container or annual | Move pot indoors before first frost |
| 3 to 5 | Container or annual only | Overwinter indoors under a grow light, or restart each spring |
How do you plant and care for lemon grass?
Plant lemon grass in spring after the last frost in full sun, in well-drained, rich loam with consistent moisture. Space plants about 24 inches apart in a bed, or use a pot at least 12 inches across (a 5-gallon container works well). It is a heavy feeder, so give it a high-nitrogen or balanced soluble fertilizer through the growing season and never let it dry out completely.
Follow this order when you set up a new plant:
- Wait until soil is warm and all frost risk has passed; lemon grass hates cold soil.
- Pick a full-sun spot, ideally 6 or more hours of direct light, with rich, well-drained loam.
- Space plants 24 inches apart in-ground, or pot one start per 12-inch (or larger) container with drainage holes.
- Water in well, then keep the top inch of soil moist; in dry or windy climates, mist the foliage.
- Feed every few weeks during active growth (the Utah State University Extension suggests a half-strength balanced soluble fertilizer weekly from June through September).
- Watch for the slow spring start, then expect rapid clumping once summer heat sets in.
Lemon grass shares the same heavy-nitrogen appetite as turf, but the timing differs. If you want the underlying logic on nitrogen rates, our NPK fertilizer guide explains what the bag numbers mean before you over-apply.
When and how do you harvest lemon grass?
Harvest a stalk once its base is at least half an inch thick, cutting it off at ground level. Take the outer, mature stalks first and leave the center to keep growing. You can harvest any time through the season once stalks reach that thickness, and most gardeners do a larger cut at the end of the season just before the first fall frost.
The tender pale base of the stalk is the part used in cooking; the tough green blades are too fibrous to eat but make a fine tea or stock. Trim off the woody top and the roots, peel the outer layers, and use or freeze the lower few inches. Lemon grass freezes well whole, which is the simplest way to bank a fall harvest.
How do you overwinter lemon grass?
Outside zones 8 to 11, overwinter lemon grass indoors by potting it up before the first frost. You have two paths: keep it growing in a sunny window or under lights, or hold it dormant in a cool, dark spot. Either way the goal is to keep the roots alive until spring, not to keep harvesting.
The active-growth method: dig up a few stalks, trim the tops to a few inches, pot them in a small container, and set them in a bright, south-facing window. Keep the soil barely moist and ease off fertilizer until you move it back outside after the last spring frost. Bonnie Plants outlines this same trim-and-pot approach.
The dormant-storage method: pot the plant and store it in a cool, dark place like a basement, watering only a few times all winter to keep the roots from drying out. The plant will look dead and that is expected. Return it to light and water in spring and it pushes new growth. Both methods beat buying a new plant every May.
Does lemon grass really repel mosquitoes?
A lemon grass plant sitting on the patio does almost nothing to repel mosquitoes. The repellent compound, citral, stays locked inside the leaves until you crush them and apply the oil to skin. Even then the protection is short. In a study published in the journal Phytomedicine (Vol. 9, Issue 3), topical lemongrass-oil preparations gave 50 percent or greater repellency lasting only 2 to 3 hours.
The plant most people actually want for mosquito work is a different species. Citronella grass, Cymbopogon nardus or Cymbopogon winterianus, is the source of commercial citronella oil. It is bigger, reaching up to 6 feet tall and 4 to 5 feet wide, with reddish stem bases, while culinary lemon grass stays green to the base and tops out around 2 to 4 feet. They are cousins, not the same plant.
| Trait | Lemon grass (C. citratus) | Citronella grass (C. nardus / winterianus) |
|---|---|---|
| Primary use | Cooking, tea, stock | Citronella oil for repellents |
| Stem base color | Green to the base | Reddish, especially new growth |
| Mature size | 2 to 4 ft (clumps to ~5 ft) | Up to 6 ft tall, 4 to 5 ft wide |
| Blade width | About half an inch | Over an inch |
| Edible | Yes, tender stalk base | Not used as food |
If your real goal is fewer mosquitoes in the yard, plant placement matters less than removing standing water and using a tested topical repellent. A pot of either grass by the door is a scent at best, not a barrier.
Common lemon grass problems and fixes
Most lemon grass trouble traces to cold, soggy soil, or underfeeding. Browning blade tips usually mean a cold snap or dry wind, not disease. Yellowing across the whole clump points to too little nitrogen or waterlogged roots. Lemon grass is otherwise tough and largely pest-free, which is part of why it works as a low-maintenance ornamental.
If a container plant gets crowded and woody in the center after a couple of seasons, divide it in early spring. Use a sharp spade to slice the root clump like a pie, then replant the outer divisions and discard the tired center. Division also gives you free plants and is the fastest way to expand a planting.
For a yard where you are choosing feature plants and grasses together, our yard design guide covers how to place clumping grasses for structure, and our seasonal grass schedule helps you line up planting and cutbacks by climate.
Last reviewed: June 2026
HMNDP Editorial Team, reviewed by HMNDP turf and horticulture editors.
Frequently asked questions
What growing zone does lemon grass need?
Lemon grass survives winter as a perennial only in USDA hardiness zones 8 and warmer, and grows reliably outdoors in zones 9 to 11. In zone 8a and colder it is treated as an annual or dug up and brought indoors before frost. Growth stalls below about 50 degrees Fahrenheit, and a hard freeze kills the top of the plant.
Is lemon grass a lawn grass?
No. Lemon grass (Cymbopogon citratus) is a tropical clumping culinary herb, not a turf grass. It forms a fountain-shaped clump 3 to 5 feet tall that you harvest rather than mow. It belongs in a garden bed or container, sited like an ornamental grass. For a low-water lawn replacement, look at native grasses and ground covers instead.
How do you harvest lemon grass?
Harvest a stalk once its base is at least half an inch thick, cutting it at ground level. Take the outer, mature stalks first and leave the center to keep growing. You can harvest any time once stalks reach that thickness, and most gardeners do a larger cut just before the first fall frost. Use the tender pale base and freeze the rest.
How do you overwinter lemon grass?
Outside zones 8 to 11, pot lemon grass before the first frost and either keep it growing in a sunny window or hold it dormant in a cool, dark spot like a basement. Trim the tops to a few inches, keep the soil barely moist, ease off fertilizer, and move it back outdoors after the last spring frost. The goal is keeping roots alive, not harvesting.
Does lemon grass repel mosquitoes?
Barely. A lemon grass plant on the patio does almost nothing because the repellent compound, citral, stays inside the leaves until crushed and applied to skin. In a Phytomedicine study, topical lemongrass-oil preparations gave 50 percent or greater repellency for only 2 to 3 hours. Removing standing water and using a tested repellent works far better.
What is the difference between lemon grass and citronella?
They are related but different species. Culinary lemon grass is Cymbopogon citratus, green to the base, 2 to 4 feet tall, with half-inch blades. Citronella grass is Cymbopogon nardus or winterianus, the source of citronella oil, with reddish stem bases, blades over an inch wide, reaching up to 6 feet tall and 4 to 5 feet wide. Only lemon grass is used as food.
How far apart do you plant lemon grass?
Space lemon grass plants about 24 inches apart in a garden bed, or grow one start per container at least 12 inches across, such as a 5-gallon pot with drainage holes. Plant in spring after the last frost in full sun, in rich, well-drained loam, and keep the top inch of soil moist while it establishes through summer.
Why is my lemon grass turning brown or yellow?
Browning blade tips usually mean a cold snap or dry wind, not disease. Yellowing across the whole clump points to too little nitrogen or waterlogged roots. Lemon grass is a heavy feeder, so feed through the growing season and keep soil moist but never soggy. If the center turns woody after a couple of seasons, divide the clump in early spring.