How to Grow Lemongrass in Pots: USA Guide

Photo: Wikimedia Commons

Lemongrass is the tropical grass that turns a patio pot into a Southeast Asian kitchen garden. Its citrus-scented stalks flavor curries, soups, and teas, and it grows with almost embarrassing speed in summer heat. In cold zones it is a perfect annual or a winter houseplant.

Few garden projects pay back faster than a herb patch. Fresh herbs transform ordinary cooking, cost almost nothing to grow, and most are far easier than vegetables — fewer pests, less feeding, and many shrug off drought. Whether you grow in a bed, a raised planter, or pots on a sunny step, the steps below will carry this herb from planting to a steady supply of fresh leaves.

Lemongrass is a tropical grass grown from divisions or nursery transplants, since seed is slow and the plants need a long warm season. Wait until frost danger has passed and the soil is warm, then set divisions 24 to 36 inches apart in full sun and rich, moisture-holding soil. In short seasons, grow it in a large pot from the start.

At a Glance

• Plant: Lemongrass (Cymbopogon citratus)
• Type: Herb
• Sun: Full sun
• Soil: Rich, moist soil
• Water: Loves heat and moisture
• Spacing: 24 inches
• Planting depth: Sow about half an inch deep
• Time to maturity: 100 to 120 days
• USDA zones: 9–12

Getting Started: Picking the Right Variety

Start with the end in mind: how you plan to use the herb decides what to plant. Heavy kitchen use calls for the most vigorous, productive type you can find, while a single ornamental-edible plant can be a prettier, slower variety. Check whether the herb is perennial in your zone — perennials are a one-time planting, while tender types get replanted each spring or overwintered indoors. Buy from a reputable nursery rather than a discount rack; healthy roots at planting time predict everything that follows.

Botanically this is Cymbopogon citratus, and how you start it shapes the whole season. Start seeds indoors about six weeks before your last spring frost. Move transplants into the garden about four weeks after your last spring frost. Buy healthy, stocky starts — leggy, root-bound plants never fully recover. The USDA National Agricultural Library holds deep reference material on this plant’s cultivation and history.

When and How to Plant

Get the timing right and half the battle is won. Everything below is tied to your last spring frost and first fall frost, so it works whether you garden in the North or the South. Start seeds indoors about six weeks before your last spring frost. Move transplants into the garden about four weeks after your last spring frost.

Sow about half an inch deep. Space plants about 24 inches apart. From sowing to harvest takes roughly 100 to 120 days. Firm the soil gently around seeds or roots and water everything in well — that first watering settles soil against the roots and starts growth off right.

To pin down the right week for your zip code, check your USDA zone planting dates on our planting calendar. It lists indoor sowing, transplanting, and direct sowing windows for hundreds of plants by zone, so you can plan the whole season in one sitting.

Starting Seeds Indoors

Count back about six weeks from your expected last spring frost and sow in cell packs or small pots filled with damp seed-starting mix. Cover lightly (or leave uncovered if the seed needs light), keep the mix moist but not soggy, and give warmth for germination followed by the strongest light you have — a sunny window is rarely enough, and leggy seedlings are the classic indoor failure. Harden plants off for a week before they move outside: a few hours of outdoor shade at first, building to full days. The Old Farmer’s Almanac offers practical, beginner-friendly growing advice for this crop.

Soil and Sun

Lemongrass wants full sun. Aim for at least six hours of direct sun a day — more is better for flavor, bloom, and disease resistance.

For soil, give it rich, moist soil. Drainage matters more than fertility for most herbs. If your ground stays wet after rain, build a raised bed or grow in containers with a gritty potting mix. A light top-dressing of compost in spring is plenty of food for the year. Gravel mulch around Mediterranean herbs keeps their crowns dry and reflects warmth up into the plant.

Zone-wise, it is at home in USDA zones 9 through 12. If you are at the warm edge of that range, afternoon shade and deep mulch help; at the cold edge, a sheltered microclimate near a south-facing wall can make the difference. Gardenia.net offers clear, gardener-written growing guides for this plant.

Watering and Feeding

Plan your watering around this: loves heat and moisture. Water deeply when the top couple of inches of soil dry out, and mulch to keep that moisture where the roots can use it.

When it comes to feeding herbs, restraint is a virtue. A single light feeding in spring covers nearly everything; container herbs may want a half-strength liquid feed monthly through summer. Let pots dry slightly between waterings — most herbs would rather be a touch dry than soggy. Snip often; harvesting is the best fertilizer for bushy growth. For pest and disease identification, Clemson’s Home and Garden Information Center is one of the best free resources available. Clemson Cooperative Extension has solid fact sheets on planting and care.

Care Through the Season

It is a heavy feeder and drinker, so water deeply and side-dress with compost through the warm months. Divide crowded clumps every couple of years to keep centers vigorous. It has few pests, though rust can appear on leaves in very wet weather; just trim affected blades.

A few grower tips specific to lemongrass: Tropical – start stalks indoors in cold zones and move out after all frost danger. Bring inside before first frost. With herbs, less is usually more — resist the urge to fuss, and let the plant’s natural toughness do the work.

Herbs thrive on attention, not pampering. Harvest a little every week and the plant responds with fresh growth; ignore it and it goes woody and sparse. Cut back perennial herbs by a third in midsummer if they get rangy — most bounce back with tender new leaves. In fall, pot up tender types before frost or take cuttings to root on a windowsill. UF/IFAS Gardening Solutions covers growing basics that apply well beyond Florida. You can confirm the native range and growing conditions in the USDA PLANTS Database.

Harvest

Harvest by cutting the outer stalks at the base, choosing stalks at least half an inch thick, then peel away tough outer layers to reach the tender core. Fresh stalks freeze beautifully for months. Pro tip: before the first frost, lift the clump and overwinter it in a bright indoor spot, since even a light freeze kills it.

Fresh herbs are a daily luxury once the patch is going — snip what you need, when you need it. To put some by, dry leafy herbs quickly in a warm, dark, ventilated spot; slow drying in humidity turns them brown and musty. Freezing in oil or water preserves flavor better than drying for soft herbs. Label everything; dried herbs all look alike by winter. The University of Minnesota Extension publishes detailed, research-based growing guides for home gardeners.

A Season With Lemongrass

A herb year runs itself if you keep the rhythm. Spring: clean up, divide, plant, and sow — most herbs want to be in the ground as early as frost allows. Summer: harvest weekly, which is also pruning; dry bundles hang in a dark, airy room while the flavor is at its peak. Fall: bring the tender ones inside, mulch the hardy ones, and sow a last round of cool-season annuals where winters are mild. Winter: tend the windowsill pots, use up the dried stores, and plan next year’s additions. Few garden routines are this simple or this rewarding.

Troubleshooting

Not frost-hardy; grow as an annual or overwinter indoors below zone 9. In practical terms, match the plant to your climate before you buy — fighting a plant’s nature is a losing game, while choosing one suited to your zone makes everything else easy.

Why no flavor? Herbs grown in too much shade or too much fertilizer taste weak — sun and lean soil concentrate the oils. Why brown leaf tips? Usually inconsistent watering or salt buildup in pots; flush containers occasionally. Why is it flowering? Most herbs bolt in heat or long days — pinch flowers to prolong leaf harvest, or let them bloom for the bees and harvest the seeds.

Do not aim for perfection in the first season. Get the plant in the ground at the right time, keep up with water and weeds, and you will learn more in one summer than from a shelf of books. The Missouri Botanical Garden plant profiles are excellent for checking mature size and culture.

Keep Exploring

If you enjoyed this guide, keep going with our guide to growing mugwort, our guide to growing wormwood, our guide to growing sweet cicely — and check your USDA zone planting dates on our planting calendar to plan what goes in next.

References

Old Farmer’s Almanac. (n.d.). Gardening guides. https://www.almanac.com/

Gardenia.net. (n.d.). Growing lemongrass in home gardens. https://www.gardenia.net/

Clemson University Cooperative Extension. (n.d.). Growing lemongrass in home gardens. https://clemson.edu/extension/

U.S. Department of Agriculture. (n.d.). PLANTS database. https://plants.usda.gov/home