Lemongrass at home: how to grow and overwinter a Thai favorite
A lush lemongrass plant is both beautiful and easy to grow in an outdoor pot. Lemongrass is cultivated for seasoning in two varieties: the strongly lemon-flavored East Indian lemon grass and the milder, West Indian lemon grass, which is a classic seasoning in Thai cuisine. Horticulturist Outi Tynys shares expert tips on growing and using lemongrass.
A lush lemongrass plant is showy and easy to care for in an outdoor pot, featuring gracefully arching bright-green leaves. A container also provides favorable conditions for the roots. Two varieties are grown for seasoning: East Indian lemon grass, with a strong lemon taste, and West Indian lemon grass, which offers a gentler, slightly sweet lemon flavor.
How to grow lemongrass? Here’s how to succeed!
Starting lemongrass indoors
Obtain young lemongrass plants or sow East Indian lemon grass seeds in spring. Sprinkle at least ten seeds in one pot, cover them lightly, and keep the soil adequately moist. Lemongrass germinates fastest at about 25 degrees Celsius (77 °F). Germination usually takes 2–4 weeks.
Improve growing conditions by placing seedlings in a greenhouse or a sunny spot in a pot or raised bed. Begin hardening them off when the temperature is 10–15 degrees Celsius (50–59 °F). Plant the seedlings in loose, well-draining soil, allowing it to dry slightly between waterings.
Two aromatic varieties
- These plants are primarily grown for seasoning as East Indian lemon grass (Cymbopogon flexuosus) and West Indian lemon grass (C. citratus). When choosing a variety, check the botanical name, since multiple names are used for lemongrass.
- You can also distinguish the varieties by appearance: West Indian lemon grass has thicker stalks and broader leaves than East Indian lemon grass.
- East Indian lemon grass can be propagated from seeds, though typically fewer than half germinate. West Indian lemon grass is sold only as seedlings because it produces seeds with poor germination rates.
Caring for lemongrass
Fertilize the plant by mixing slow-release fertilizer into the soil or by watering every couple of weeks with a mild nutrient solution.
Cut the first stalks once the clump has thickened and the stalks reach 20–30 centimeters (8–12 inches) in length. Harvest gradually by removing the thickest stalks at the base.
Overwintering lemongrass
Bring the plant indoors before cold weather arrives and keep it in a bright spot. Below 10 degrees Celsius (50 °F), growth slows and watering needs drop. If the temperature is 15–20 degrees Celsius (59–68 °F), regular watering is necessary. Watch the leaves for signs of mites or thrips.
Lemongrass growing season (in Finland)
- Sowing (East Indian lemon grass) in February–March.
- Transplant outdoors (with frost protection) from mid-May to late June.
- Harvest in July–September.
- Overwinter in a cool space from September–December.
West Indian lemon grass is a classic seasoning in Thai cuisine.
Using lemongrass in cooking
- Cut whole stalks from the plant. The most intense lemon flavor is in the tender, juicy base, which can be left in dishes or finely chopped. This method is ideal for West Indian lemon grass, which has thicker stalks.
- You can add the base of both varieties to dishes in large pieces during cooking and remove them before serving. The same applies to the long, coarse leaves. Beyond savory dishes, the harvest is also perfect for drinks like tea or iced tea.
- Fresh stalks and leaves offer the most aroma, but you can freeze or dry them as well.
