Growing Culinary Lemongrass at Home: Seeds, Cuttings, Pots, and Indoor or Outdoor Care

Lemongrass (Cymbopogon citratus) is a tropical herb with tall, slender, gray-green stalks and a bright, citrusy aroma that is essential in Thai cooking. You can grow it at home from seed, but it is easier and faster to propagate from fresh stalks, either in water or directly in soil. It thrives in warm, sunny conditions, either in a container or in the ground, and can be kept indoors if given enough light. This guide covers starting lemongrass from seed and cuttings, growing it in pots, and caring for it indoors and outdoors, including tips for challenging climates like Arizona and Georgia.

What is Culinary Lemongrass?

Culinary lemongrass (Cymbopogon citratus) is a clumping tropical grass that forms dense, fountain-like mounds of arching, blade-like leaves. The edible portion is the thickened, bulbous base of the stalk, which is pale yellow to white with a slight pinkish tinge and has a firm, fibrous texture. When bruised or cut, it releases a bright, lemony fragrance with hints of ginger and mint. Unlike other ornamental lemongrass varieties, Cymbopogon citratus is preferred for cooking because of its tender inner core and strong, clean citrus flavor without harsh or bitter notes. In Thai cuisine, it is usually sliced finely or pounded into a paste for dishes like tom yum soup and green curry, where it adds a fresh, aromatic top note.

How to Grow Lemongrass from Seed

Growing lemongrass from seed is possible but requires patience, as germination can be slow and erratic. Start seeds indoors 6-8 weeks before the last expected frost in your area.

1. Prepare the tray: Fill a seed-starting tray or small pots with a light, well-draining seed-starting mix. Moisten the mix thoroughly.
2. Sow the seeds: Sprinkle the tiny seeds on the surface and press them gently into the soil. Do not cover them deeply; lemongrass seeds need light to germinate, so a very thin dusting of fine vermiculite or no covering at all is best.
3. Create a mini greenhouse: Cover the tray with a clear plastic dome or plastic wrap to maintain high humidity. Place it in a warm spot with bright, indirect light. The ideal soil temperature for germination is 70-75°F (21-24°C). A heat mat can help maintain this.
4. Keep moist: Mist the soil surface regularly to keep it evenly moist but not waterlogged. Germination typically takes 14-25 days, but can be longer.
5. Transplant: Once seedlings are 2-3 inches tall and have at least two sets of true leaves, transplant them into individual 4-inch pots. Harden off gradually before moving outdoors.

Seed-grown lemongrass may be slower to reach harvest size than plants started from cuttings, often taking a full growing season before producing thick stalks.

How to Grow Lemongrass from Cuttings (Stalk Propagation)

The easiest and most reliable way to grow lemongrass at home is from fresh stalks purchased at an Asian grocery store or farmers market. Look for stalks with intact, plump bases and any sign of small roots.

Rooting in Water

1. Prepare the stalks: Trim the top leaves, leaving about 4-6 inches of stalk attached to the base. Remove any dry outer leaves.
2. Place in water: Put the bases in a glass or jar with about 1-2 inches of water. Ensure the bottom of the stalk is submerged but the top remains above water.
3. Provide light and warmth: Place the jar on a sunny windowsill or under a grow light. Change the water every 2-3 days to prevent rot.
4. Wait for roots: Roots should appear within 1-2 weeks. Once the roots are 1-2 inches long, transplant the stalks into soil.

Rooting Directly in Soil

1. Prepare the stalk: Same as above, but instead of water, insert the base directly into a pot filled with well-draining potting mix. Bury about 1-2 inches of the base.
2. Water and cover: Water thoroughly and place the pot in a warm, bright location. To increase humidity, you can loosely cover the pot with a clear plastic bag, but ensure some air circulation.
3. Check for growth: New green shoots should emerge from the center within a couple of weeks, indicating successful rooting.

Growing Lemongrass in Pots

Lemongrass grows well in containers, which is ideal for gardeners with limited space or for those in colder climates who need to move plants indoors for winter.

• Container size: Choose a pot that is at least 12 inches in diameter and 12 inches deep for a single plant. Larger pots (5 gallons or more) will allow the plant to grow bigger and produce more stalks.
• Drainage: The pot must have drainage holes. Lemongrass does not tolerate waterlogged soil, which can lead to root rot.
• Soil: Use a high-quality, well-draining potting mix. A blend of potting soil, perlite, and compost works well.
• Watering: Keep the soil consistently moist but not soggy. Water when the top inch of soil feels dry. In hot, dry weather, containers may need daily watering.
• Fertilizing: Feed every 4-6 weeks during the growing season with a balanced liquid fertilizer or top-dress with compost.

Growing Lemongrass Indoors

Lemongrass can be grown indoors as a houseplant, but it requires bright light to thrive.

• Light: Place the pot near a south- or west-facing window where it receives at least 6 hours of direct sunlight daily. If natural light is insufficient, use a full-spectrum grow light for 12-16 hours per day.
• Temperature and humidity: Lemongrass prefers temperatures between 65-85°F (18-29°C) and appreciates moderate humidity. A pebble tray or humidifier can help in dry indoor air.
• Watering: Keep the soil evenly moist but reduce watering slightly in winter when growth slows.
• Harvesting indoors: You can harvest outer stalks as needed, cutting them at the base. The plant will continue to produce new growth from the center.

Growing Lemongrass Outdoors: Climate and Regional Tips

Lemongrass is a tropical perennial that is hardy in USDA zones 9-11. In colder climates, it is often grown as an annual or brought indoors for winter.

Growing Lemongrass in Arizona

In Arizona's hot, dry climate, lemongrass can be grown successfully with extra attention to water and sun protection.

• Sun: While lemongrass loves sun, intense afternoon sun in Arizona's low desert (e.g., Phoenix) can scorch leaves. Provide light shade during the hottest part of the day, or plant where it gets morning sun and afternoon shade.
• Watering: The dry air causes rapid evaporation, so water deeply and frequently, especially during the summer. Mulching around the plant helps retain soil moisture.
• Soil: Amend native soil heavily with compost and organic matter to improve water retention, or grow in a large container with potting mix.
• Winter care: In colder areas of Arizona (like Flagstaff), lemongrass will not survive winter outdoors. Grow in pots and move indoors before temperatures drop below 40°F (4°C).

Growing Lemongrass in Georgia

Georgia's hot, humid summers and mild winters make it possible to grow lemongrass as a perennial in coastal and southern parts (zones 8b-9), but it needs protection in northern areas.

• Sun: Full sun is best in Georgia to encourage robust growth and essential oil production.
• Watering: Regular rainfall may be sufficient, but during dry spells, water deeply once a week.
• Soil: Lemongrass grows well in Georgia's clay soils if amended with organic matter to improve drainage. Raised beds or containers are also good options.
• Winter care: In USDA zone 8a and colder, lemongrass is not reliably hardy. In zone 8b and above, mulch heavily with straw or leaves in late fall to protect the crown. In colder regions, dig up divisions in fall, pot them, and overwinter indoors.

Comparison: Growing Lemongrass from Seed vs. Cuttings

Harvesting and Using Lemongrass

You can begin harvesting lemongrass when the stalks are at least 1/2 inch thick, usually 3-4 months after planting cuttings. Use a sharp knife to cut individual stalks at the base, or pull them outward and downward. The inner, tender part at the bottom of the stalk is what you use for cooking. Remove the tough outer leaves and the upper green part (which can be saved for teas or broths). The inner core can be finely chopped, pounded into a paste, or added whole to soups and curries and removed before serving. Fresh lemongrass can be stored in the refrigerator for a few weeks or frozen for several months.