Lemongrass

Overview

Lemongrass forms dense, fragrant clumps that keep growing year after year. The stalks flavor food and tea, and the leaves can be cut repeatedly for mulch. Planted along bed edges, it makes a tidy living border.

History

Lemongrass is native to tropical Asia and is a key ingredient in Thai, Vietnamese, and other Southeast Asian cooking. It is a common backyard plant in Hawaiʻi.

Growing on Kauaʻi

• Grows in all rainfall zones in full sun; tolerates drought once established.
• Prefers well-drained soil.

Planting and propagation

• Divide an existing clump, keeping some roots on each piece, or root store-bought stalks with an intact base in a glass of water.
• Trim the leaves short and plant divisions about 2–3 ft apart.

Care and maintenance

• Cut back old, brown leaves once or twice a year and use them as mulch.
• Divide large clumps every couple of years to keep them vigorous.

Role in the guild

Lemongrass lines the edges of beds and paths, helping block creeping grasses. In the drier leeward guild it grows with chaya and sissoo spinach.

Harvest

Cut or twist off outer stalks at the base when they are about ½ inch thick. Use the tender lower part for cooking and the leaves for tea.

Uses

• Food and drink: stalks in curries, soups, marinades, and stir-fries; leaves for tea.
• Soil: leaves make long-lasting mulch.
• Structure: a living edge that helps hold soil on bed borders.

Problems to watch

• Few pests. Clumps can get woody and dead in the center if never divided.
• Leaf edges are sharp; wear gloves and long sleeves when cutting.

General guidance for Kauaʻi; conditions vary by site. Check any new plant at plantpono.org before planting.