Growing Lemongrass
Lemongrass (Cymbopogon citratus) is a tropical grass with tall, arching leaves and thick, bulbous stalks that carry a bright, lemony aroma. It is a cornerstone ingredient in Thai, Vietnamese, Indonesian, and Malaysian cooking. In the garden, it forms a handsome clump 3–5 feet tall and has the added benefit of repelling mosquitoes.
Getting Started
The easiest way to start lemongrass is from stalks bought at an Asian grocery store. Look for stalks with intact bases. Trim the tops to about 4 inches, peel away any dry outer layers, and place the base in a jar of water on a sunny windowsill. Change the water every few days. Within 2–3 weeks, roots will appear. Once roots are an inch or two long, transplant into a pot or garden bed.
You can also buy nursery starts, but the grocery store method is cheaper and works very reliably.
Growing Conditions
Lemongrass is tropical and thrives in full sun, heat, and humidity. It needs at least 6 hours of direct sun and rich, well-draining soil. It is a heavy feeder — mix compost into the planting hole and apply a nitrogen-rich fertilizer monthly during the growing season. Water generously; lemongrass likes moist (not waterlogged) soil.
In zones 9–11, lemongrass can stay outdoors year-round. In cooler zones, treat it as an annual or grow it in a large container (at least 5 gallons) and bring it inside before frost. A heated garage or sunroom that stays above 40°F is sufficient for winter dormancy. See Overwintering Herbs.
Harvesting
Begin harvesting once the stalks are at least half an inch thick at the base. Cut or twist individual stalks off at the base of the clump. The usable portion is the lower 4–6 inches of the stalk — the tough, pale section near the root. Peel away the outer layers until you reach the tender, fragrant core. The upper green leaves can be used for tea but are too tough for cooking.
Culinary Uses
Lemongrass is used in Thai tom yum and tom kha soups, Vietnamese pho, Malaysian laksa, and Indonesian satay marinades. The stalks can be bruised and added whole to soups (then removed before serving) or sliced very thin and minced for curry pastes. For beverages, steep the leaves or bruised stalks in boiling water for a refreshing herbal tea.