This tender perennial from southeast Asia is one of the most highly scented herbs. For best success with its longevity, grow clumps in pots that can be moved in the cool season to a protected location where it will not suffer from winter’s cold. Lemon grass is damaged when temperatures drop into the 40’s.
- Purchase young plants from a nursery for the fastest and easiest way to introduce lemon grass into your garden.
- Or, at home, root 2-3 plump, healthy lemon grass stalks with a bulbous bottom. You can find them in a grocery store produce section or an Asian market.
- Pull back a thin layer at the bottom and put stalks in a tall container with 3-4 inches of water and place near a window for ample light.
- Check water level every 1-2 days and change to fresh water once a week.
- Watch for roots to form in 2-3 weeks; pot up in a gritty soil mix after you see 3-4 roots. Soil must be moist, not soggy. Move pots outdoors into morning sun in warm weather.
- When lush, green sprouts appear at the tops of stalks, transplant into a larger pot or in the ground in a sunny location with fast-draining soil.
- New vigorous stalks will emerge within three months.
- Or start seeds by scattering them thinly over a sterile germination mix.
- Gently press down the very tiny seeds but do not cover them. Use a mist sprayer to keep moist until germination, usually within 2 weeks.
- Gently snip off extra seedlings to avoid damaging neighboring roots.
- When seedlings are 3 in. tall, transplant into a 4-in. pot until they are large enough to move into the garden or into a more permanent 15-in. container.
- Lemon grass is fast growing to 3-4 ft. or taller with a mass of wide, green grass. It requires at least 1 sq. ft. of space with clumps about 2 ft. apart. A single plant is usually enough.
- Soil must be loose, fast-draining, and watered regularly to prevent drying out; fertilize once/month. Overwatering and soggy conditions cause rot.
- Keep an eye on spreading plants that can quickly outgrow a container or allotted garden space.
- In mild winter areas, cut back grass to about 6 in. when plants are dormant or nearly so. Growth resumes as the weather warms.
- Dig up small clumps in cold winter areas and move plants indoors in pots to protect from hard frosts and freezes. Move container-grown plants to protected areas.
- Divide clumps in spring every few years to control size.
- When grass clumps reach at least 12 in. tall and develop 1-2 dozen stalks, begin harvesting.
- Use a trowel to dig out stalks with a fan of leaves and trim roots; or cut stalks at ground level with a knife or shears just below the bulbous base above the roots.
- Harvest no more than 1/3 of a clump at a time. The bulbous base is the most flavorful and tender part of the plant but must be smashed in the kitchen before using in recipes.
- Cautions: Wear gloves to protect hands from sharp edges of grass. Dogs, cats, and horses may experience stomach upset if they eat large amounts of lemon grass.