How to Grow Lemongrass: Planting, Care, and Uses

Lemongrass is an ornamental grass commonly utilized as an herb, often used in cooking, aromatherapy, soaps, and candles. Clumps of lemongrass form from bulbs and feature coarse, wide leaves. This tropical or subtropical perennial can be grown in the ground, in containers, or even in water. It's often grown as an annual in temperate zones. Note that this plant is toxic to pets.

How to Plant Lemongrass

When to Plant

Wait until the danger of frost has passed before planting lemongrass, preferably once nighttime temperatures consistently hit 60°F. To start from seed indoors, sow in flats three weeks before the last frost in your growing zone.

Where to Plant

Choose a spot in full sun with good drainage. Lemongrass won't grow well in clay and needs rich, fertile, loose soil. Add sand or consider planting in pots or raised beds if your garden soil is unhealthy. A location protected from strong winds reduces breakage and flattening.

How to Plant

In ideal conditions, lemongrass may grow to 6 feet tall and 4 feet wide, so leave 2 to 3 feet between plants. The planting technique is similar to planting onion slips. Set the grass so the bottoms of the bulbs rest just at the soil line, with roots buried.

Care

Lemongrass grows with abundance in areas where conditions mimic the tropical habitat of their origin. This popular herb prefers full sunlight, moist but well-draining soil, and moderate watering.

Light

Plant lemongrass in an area that gets full sun, even in hot climates. At least six hours of direct sun per day will meet the plant's energy needs. Plants growing in shade will be sparse and may attract pests.

Soil

Prepare rich, loamy soil for lemongrass. Create ideal soil by adding organic amendments like compost, manure, and leaf mold before or at planting time.

Water

Water lemongrass once or twice weekly to keep the roots constantly moist. Lemongrass is not drought-tolerant and requires regular irrigation throughout the growing season. A 3-inch layer of mulch conserves soil moisture. Potted plants may need to be watered daily.

Temperature and Humidity

Protect lemongrass from freezing temperatures, as it is frost-sensitive and won't survive temperatures below 15°F. Bring potted plants indoors when temperatures drop below 50°F.

Fertilizer

Feed lemongrass weekly throughout the peak growing season with a nitrogen-rich fertilizer or add a slow-release product with an NPK 6-4-0 at planting time. Alternatively, supplement nutrients by watering with manure tea or add a nitrogen booster such as blood meal.

Harvesting

Use a hand trowel to remove individual stalks, roots, and all, from the clump. Remove the tough outer leaves and prepare the tender white stalks by chopping, or freeze whole stalk pieces for later use. A fast-growing plant, lemongrass can withstand harvest when plants are young.

Types of Lemongrass

Though there are many species of lemongrass, two are interchangeably used in the United States: West Indian and East Indian lemongrass. These two species are edible, while citronella grass (which is in the same genus) is not.

• West Indian lemongrass (C. citratus) is most favored for culinary use.
• East Indian lemongrass (C. flexuosus) is most favored for aromatherapy, perfumes, and soaps.
• Citronella grass (C. nardus) is related to lemongrass but is not an edible grass species; used as insect repellent in candles and oils and as an ingredient in soap.
  

Pruning

Shear your plants to about 6 inches high at the end of winter, when they are in their resting phase. You'll also want to remove any dead, dried-up leaves with clean pruners to make way for new growth. Lemongrass plants rebound quickly and send up new shoots when warm weather returns.

Propagating Lemongrass

You can easily propagate lemongrass in water. Cut a stalk, removing any leaves, and then place it in a glass of water with the bulb facing downward. Place the glass in a sunny spot and change the water every few days. Once roots have emerged and reach 2 to 3 inches in length, transplant into soil.

How to Grow Lemongrass From Seed

Start Indoors

Start seeds indoors three weeks before the final frost in your area. Press them 1/8 inch deep into a flat filled with sterile potting mix. Do not cover as these seeds need light to germinate. Place the flat in a warm sunny location and keep moist until germination occurs.

Direct Sow

Direct sow seeds in the garden once air temperatures reach 60°F. Plant seeds 1/8 inch deep and one inch apart. Keep seeds moist until germination occurs in about two weeks. Thin seedlings to 1 foot apart when they are 3 inches tall.

Potting and Repotting Lemongrass

Choose a large pot that is 12 inches wide and deep or a 5-gallon container to support a healthy root system and keep top-heavy plants from tipping over. Use high-quality commercial potting soil premixed with time-released fertilizer. Repot with fresh potting mix in spring.

Overwintering

To maintain lemongrass as a perennial in temperate zones, plant it in containers that can be moved indoors in winter. Large container plants can be sheared down to 6 inches and kept in a basement or unheated garage. They won't need much except an occasional watering.

Bring plants indoors when nighttime temperatures drop below 50°F. Wait to move them back outdoors in spring until after your frost-free date.

Common Pests & Plant Diseases

Lemongrass isn't usually troubled by diseases or insects, but can attract pests common to most ornamental plants. Knock down aphids and spider mites with a spray from your garden hose or apply horticultural oil for infestation.

In some areas, rust fungus can affect lemongrass plants. Symptoms include brown spots or streaks on leaves, leading to plant death. Prevent rust by watering plants at the soil level.

Pests to Watch

Look out for aphids, which will look like tiny, pear-shaped insects that are light green, red, black, or yellow. To remove them, you can spray insecticidal soap or treat the plant with neem oil.

From: thespruce