The fragrant herb, lemongrass (Cymbopogon citratus), is popular in both culinary dishes and home gardens due to its distinct, citrusy aroma and flavor. This perennial grass is native to tropical regions but can be grown in many climates by treating it as an annual or bringing it indoors during colder months. Establishing your own supply does not require starting from seed, which is often inconsistent. Instead, lemongrass offers two practical methods for home propagation using existing plant material: rooting harvested stalks in water and dividing a mature clump.
Essential Preparation and Timing
The success of propagating lemongrass requires choosing the right time and starting material. The ideal window is late spring or early summer, specifically after the last expected frost date when temperatures are reliably warm. Propagating too early can result in slow or failed root development, as this tropical plant thrives in heat and ample sunlight.
When propagating from fresh stalks, select firm, healthy stems that have the entire basal plate intact. This base, often called the root crown, is where new roots will emerge and is necessary for success. Avoid stalks that appear dry, soft, or have a damaged or missing base, as they will not generate new growth. For propagation by division, ensure you use a mature clump that has been growing for at least one full season.
Step-by-Step: Rooting Lemongrass Stalks in Water
Propagating lemongrass from fresh stalks is a simple method to start a new plant from a store-bought cutting. Prepare the stalk by gently peeling back any dry, fibrous outer layers to expose the plump, white base. If the bottom is woody or damaged, use a sharp knife to slice a thin sliver off the base to expose fresh tissue, ensuring the root crown remains intact.
Place the prepared stalks upright in a glass or jar with one to two inches of clean water, covering only the bottom nodes. Position the container in a warm location that receives bright, indirect sunlight, such as a kitchen windowsill. Change the water every one to two days to prevent the growth of mold, fungus, or bacteria that could cause the cutting to rot.
Within one to three weeks, small, white roots should emerge from the basal plate, often accompanied by new green growth sprouting from the top. Allow the roots to grow to a length of at least one to two inches before transplanting into soil. Waiting until the roots are well-developed ensures the young plant has a stronger foundation to absorb water and nutrients.
Step-by-Step: Propagating Lemongrass by Division
Propagating by division offers a faster route to an established plant since it utilizes an existing root system. This method is best performed when the mature clump is actively growing, typically in the spring or early summer. Prepare the parent plant by cutting back the foliage to a height of six to ten inches to reduce water loss and make the clump easier to handle.
Carefully dig around the base of the mature clump, six to eight inches out from the stalks, and lift the entire root ball from the soil. Separate the mass into smaller sections, often called slips, using a sharp spade, knife, or your hands. Each slip must contain at least two or three healthy stalks along with a substantial portion of the root and rhizome system attached to ensure successful regrowth.
Remove any dead or withered stalks and trim away excessively long or damaged roots to encourage fresh development. These newly separated slips are ready for immediate replanting in their new location or containers.
Ensuring Success: Transplanting and Initial Care
The transition into soil requires a specific environment for both water-rooted cuttings and divided slips to thrive. Select a container with good drainage or a garden spot that receives a minimum of six to eight hours of full sun daily. Lemongrass requires rich, well-draining soil, so amend the planting site with organic compost or well-rotted manure for fertility and structure.
Plant the rooted stalks or slips so the root crown is just below the soil surface, taking care not to bury the entire stem, which can lead to rot. Immediately after transplanting, water the plant thoroughly to settle the soil around the roots and eliminate air pockets. For the first few weeks, maintain consistently moist soil, ensuring it is never waterlogged, to help the new root system establish.
Lemongrass is sensitive to cold and must be protected from temperatures below 45 degrees Fahrenheit, especially during establishment. If you live in a region with frost, growing the plant in a container allows for easy relocation indoors when cooler weather arrives. Once established, the plant benefits from regular watering and a high-nitrogen fertilizer throughout the active growing season.