Lemongrass is one of those ingredients that transforms a dish the moment it goes in. That bright, citrusy, slightly floral aroma is the foundation of Thai, Vietnamese, Indonesian, and Malaysian cooking — essential in tom yum, laksa, curry pastes, lemongrass chicken, and dozens of other dishes. Grocery store lemongrass costs 3 to 4 dollars for a few stalks, most of which end up in the compost because only the tender lower portion is usable. Growing your own lemongrass gives you an unlimited supply of fresh stalks, the outer leaves for tea, and a stunning ornamental grass that looks beautiful in the garden or on a patio.
The challenge is that lemongrass (Cymbopogon citratus) is a tropical grass native to South and Southeast Asia. It thrives in heat and humidity and has zero tolerance for frost. In USDA zones 10 and above, it grows as a year-round perennial that can reach 5 to 6 feet tall and 4 feet wide — an impressive, fountain-shaped clump that looks nothing like the sad little stalks in the grocery store produce section. In zones 9 and below, lemongrass is an annual or a container plant that must be brought indoors for winter.
Despite its tropical origins, lemongrass is remarkably easy to grow in temperate climates. It grows fast in warm weather (a single stalk planted in May becomes a substantial clump by September), it has no significant pest or disease problems, and it can be started from grocery store stalks for the cost of a single purchase. If you eat any amount of Southeast Asian food, growing your own lemongrass is one of the highest-return herb investments you can make.
Starting Lemongrass from Grocery Store Stalks
This is the easiest and cheapest way to get started. No nursery trip, no seed order, no waiting. You can turn a 3-dollar bundle of grocery store lemongrass into a dozen plants.
What to Look For
Buy the freshest lemongrass available. Look for stalks that are firm (not dried out or limp), have a visible bulb at the base, and ideally still have a trace of root nubs at the very bottom. The base should be light green to white, not brown or mushy. Asian grocery stores typically have the freshest lemongrass — they turn over stock faster and the stalks are often more recently harvested than what you find at mainstream supermarkets.
Rooting Method
- Trim each stalk to about 6 inches, cutting off the dry upper portion. Peel away any dry or dead outer layers to expose the fresh inner core.
- Place the stalks in a glass of water, root end down, with 2 to 3 inches of stalk submerged. Set on a sunny windowsill.
- Change the water every 2 to 3 days to prevent bacterial growth.
- Roots appear in 1 to 3 weeks — thin white threads emerging from the base. New green growth often appears from the top at the same time.
- Once roots are 1 to 2 inches long and new leaves are growing, the stalks are ready to plant.
Success rate is typically 70 to 80 percent. Not every stalk will root — some have been in cold storage too long or have had the growth point damaged during harvesting. Start with 5 or 6 stalks to ensure you get at least 3 or 4 viable plants.
Planting and Growing Conditions
Lemongrass wants heat, sun, moisture, and rich soil — the opposite of what Mediterranean herbs like rosemary and thyme prefer. Think of it as a vegetable rather than a herb in terms of care requirements.
In-Ground Planting (Zones 9-11)
- Sun: Full sun — 6 to 8 hours minimum. More sun equals faster growth and stronger citrus flavor.
- Soil: Rich, fertile, moist, well-draining. Amend with 3 to 4 inches of compost before planting. Lemongrass is a heavy feeder that benefits from fertile soil — the opposite of the lean-soil approach for oregano and sage.
- Spacing: 24 to 36 inches apart. Each plant becomes a substantial clump — 3 to 4 feet wide at maturity. Underestimating the spread is the most common mistake.
- Watering: Consistent moisture. Water deeply 2 to 3 times per week during dry periods. Lemongrass is a tropical grass that drinks heavily — it will signal drought stress by rolling its leaves inward along the midrib.
- Fertilizer: Feed monthly with a balanced fertilizer or side-dress with compost every 4 to 6 weeks during the growing season. Lemongrass grows fast and depletes soil nutrients quickly.
Container Growing (All Zones)
Container culture is the standard approach for zones 8 and below because it allows you to move plants indoors for winter.
- Pot size: Minimum 14 inches in diameter and 12 inches deep. A 5-gallon nursery pot or a half whiskey barrel works well. Lemongrass in too-small a pot becomes rootbound quickly, which stunts growth and reduces stalk size.
- Potting mix: Standard potting soil amended with extra compost. Lemongrass is not particular about soil composition as long as it is fertile and drains.
- Watering: Containers dry out fast in summer heat. Water daily during hot weather — lemongrass in pots may need water every single day when temperatures exceed 85 degrees. A saucer under the pot is fine; lemongrass tolerates slightly wet feet better than most herbs.
- Fertilizer: Liquid feed every 2 weeks during the growing season. Container plants deplete nutrients faster than in-ground plants.
If you grow other herbs in containers, group lemongrass with moisture-loving herbs like mint, parsley, and chives rather than with dry-soil Mediterranean species. Or simply give lemongrass its own large pot — it will fill it impressively by midsummer.
Overwintering in Cold Climates
Lemongrass is killed by any hard frost (28 degrees Fahrenheit or below). In zones 8 and below, you must bring it indoors for winter or treat it as an annual.
Indoor Overwintering
- Before the first frost (usually mid-October in zones 6-7, late October in zone 8), cut the foliage back to 6 to 12 inches tall.
- If the plant is in the ground, dig up the entire clump, shake off excess soil, and pot it in the largest container that will fit in your indoor space.
- Bring the pot indoors to a bright location — a south-facing window, a sunroom, or under grow lights. Lemongrass goes semi-dormant in winter with reduced light and cooler temperatures, but it needs to stay above 40 degrees at all times.
- Reduce watering to once a week or when the top 2 inches of soil are dry. The plant is not actively growing and needs much less water than during summer.
- Do not fertilize during winter dormancy.
- In spring, after the last frost and when nighttime temperatures are consistently above 50 degrees, move the plant back outdoors. Increase watering and resume fertilizing. New growth appears quickly once the heat returns.
Dormant Storage (Minimal Space Method)
If you do not have a bright indoor spot, lemongrass can be overwintered in a cool, dark location (garage, basement, unheated room) at 40 to 55 degrees. Cut the foliage back to 2 to 3 inches above the soil. Water very sparingly — just enough to keep the roots from completely desiccating (once every 3 to 4 weeks). The plant looks dead all winter. In spring, move it to light and warmth, water thoroughly, and new growth emerges from the base within 1 to 2 weeks. This method has a lower success rate (about 60 to 70 percent) than bright indoor overwintering, but it works when space and light are limited.
Harvesting and Kitchen Prep
Lemongrass is ready to harvest when stalks are at least 1/2 inch thick at the base — typically 3 to 4 months after planting. The thicker the stalk, the more tender, flavorful inner core you get.
How to Harvest
Grasp a stalk firmly at the base and twist while pulling. It should snap free from the clump cleanly. Alternatively, cut the stalk at soil level with a sharp knife. Harvest outer stalks first — these are the oldest and thickest. Leave the inner stalks to continue growing. A mature clump can sustain harvests of 2 to 3 stalks per week throughout the growing season without being diminished.
Using the Whole Stalk
Most recipes use only the bottom 4 to 6 inches of the stalk — the pale, tender portion. But every part of the lemongrass stalk is usable:
- Bottom 4-6 inches (bulb end): This is the culinary gold. Peel away the tough outer layers until you reach the pale, slightly purple-tinged inner core. Slice thinly, mince, or pound with a mortar and pestle for curry pastes, stir-fries, and soups.
- Upper stalk (woody middle section): Too tough to eat directly, but full of flavor. Bruise with the back of a knife and add whole to soups, broths, and curries. Remove before serving, like a bay leaf.
- Leaves (top green portion): Make excellent tea. Steep a handful of fresh or dried leaves in boiling water for 5 to 10 minutes. Lemongrass tea has a clean, citrusy flavor and is traditionally used in Southeast Asian and Caribbean cultures as a calming, digestive tea. The tea garden guide includes lemongrass among the best homegrown tea herbs.
Storing Fresh Lemongrass
Whole stalks keep for 2 to 3 weeks in the refrigerator wrapped in a damp paper towel inside a plastic bag. For longer storage, freeze whole stalks in freezer bags for up to 6 months — the flavor holds remarkably well. Frozen lemongrass can be sliced directly from frozen without thawing. You can also mince fresh lemongrass and freeze it in ice cube trays with a splash of water, following the same method described in the herb preservation guide.
Companion Planting and Mosquito Deterrence
Lemongrass contains citronella — the same compound used in citronella candles and mosquito repellents. While a living lemongrass plant does not produce enough airborne citronella to create a mosquito-free zone on its own, there is some evidence that large clumps near seating areas contribute to reduced mosquito activity, especially when combined with other aromatic plants. At minimum, crushing a leaf and rubbing it on exposed skin provides short-term insect deterrence.
In the garden, lemongrass makes a good companion for vegetables and other herbs because its strong scent may confuse pest insects looking for their host plants. Its tall, fountain-like form also provides light shade for heat-sensitive crops planted on its north side — lettuce, spinach, and cilantro can benefit from afternoon shade cast by a mature lemongrass clump.
Propagation by Division
Once your lemongrass clump is established (usually by the end of the first growing season), you can divide it to create new plants. Division is the standard propagation method because lemongrass rarely sets seed in temperate climates.
In spring, dig up the entire clump or tip the container. Pull or cut the clump into divisions, each with 3 to 5 stalks and attached roots. Replant divisions immediately and water thoroughly. Each division establishes quickly and becomes a full-sized clump within one growing season. A single first-year plant can often yield 4 to 6 divisions by the following spring — more than enough to line a patio, fill a herb garden section, and give to friends.
Frequently Asked Questions
Can I grow lemongrass from seed?
Technically yes, but it is impractical for most gardeners. Lemongrass seed has a low germination rate, requires warmth (75 to 85 degrees) and patience (14 to 25 days to germinate), and the seedlings grow slowly for the first few months. Starting from grocery store stalks is faster, easier, cheaper, and more reliable. A rooted grocery stalk is already the equivalent of a 2 to 3 month old seedling in terms of growth stage.
How big does lemongrass get?
In tropical climates (zones 10-11) with year-round growth, lemongrass clumps can reach 5 to 6 feet tall and 4 feet wide. In temperate zones with a single growing season, expect 3 to 4 feet tall and 2 to 3 feet wide by the end of summer from a spring-planted stalk or division. In containers, growth is proportional to pot size — a 14-inch pot produces a 2 to 3 foot plant; a half whiskey barrel produces a near full-sized clump.
Is lemongrass invasive?
No. Unlike many grasses, lemongrass is a clumping grass — it expands slowly outward from the center but does not send runners or rhizomes across the garden. The clump gets wider over time but stays where you put it. In temperate climates, frost kills the plant before it could ever become a nuisance. In tropical climates, it can become a very large clump that is difficult to remove, but it does not spread aggressively through seeds or runners the way invasive grasses do.
Why are my lemongrass stalks thin and spindly?
Thin stalks indicate one or more of: insufficient sun (lemongrass needs full sun for thick stalk development), insufficient fertilizer (it is a heavy feeder), insufficient water (tropical grass, tropical water needs), overcrowding (too many stalks competing for resources in a small pot), or the plant was started too late in the season to reach full size before cold weather. Address sun, food, and water first. If the clump is dense with many thin stalks, divide it to give each division more room to produce thick stalks.
Can I dry lemongrass?
Yes. Slice the lower stalk thinly and dehydrate at 95 to 105 degrees until brittle, or air-dry sliced stalks in a warm, dark location for 1 to 2 weeks. The leaves can be dried whole for tea. Dried lemongrass retains good flavor for 6 to 12 months — better retention than most dried herbs because its aromatic compounds are relatively stable. However, the fresh, bright citrus note does fade somewhat with drying. For cooking, frozen lemongrass retains more of the fresh character than dried.