Lemongrass (Cymbopogon citratus) is a tropical grass prized globally for its intense citrus aroma and flavor. Originating in warm, humid regions of South Asia, this perennial herb is widely used in cooking, traditional medicine, and as an ornamental garden plant. Its growth rate is tied to the availability of heat, moisture, and light, making its development highly variable across different climates. Understanding the timelines and factors that govern its growth allows gardeners to maximize their harvest potential.
Specific Timelines for Lemongrass Growth
Lemongrass exhibits a fast-growing nature, particularly when cultivated in conditions mimicking its native tropical habitat. In frost-free environments, it is a perennial that grows continuously, but in cooler climates, it must be treated as an annual. A single plant can reach three to five feet in height in a single growing season under optimal conditions.
The time required to produce usable stalks depends on the starting method and ambient temperature. When propagated from established cuttings, the plant can yield its first harvestable stalks (at least half an inch thick) within 60 to 90 days after transplanting. Growth begins slowly in the spring but accelerates once the sustained heat and humidity of summer arrive, allowing the plant to reach its full potential before temperatures drop in the fall.
How Environmental Conditions Influence Growth Speed
The speed at which lemongrass matures is dictated by three factors: temperature, water availability, and sunlight. Lemongrass requires sustained warmth, with temperatures between 70°F and 90°F providing the ideal range for rapid stalk expansion. Growth slows significantly if temperatures consistently fall below 70°F.
Consistent and ample water is equally important, as this herb thrives in humid conditions and requires high soil moisture to fuel its growth rate. Drought conditions can inhibit the plant’s development and reduce the production of new tillers. For the fastest growth, the plant needs a minimum of six to eight hours of direct sunlight daily. Insufficient light results in slower growth, producing lanky, weaker stalks. Finally, lemongrass requires a nutrient-rich environment, specifically benefiting from nitrogen to support the rapid development of leaves and stalks.
Initial Establishment: Seeds Versus Cuttings
The initial speed of lemongrass growth is determined by the propagation method chosen. Starting the plant from seeds is the slowest approach for a quick harvest, as germination takes one to three weeks. After germination, seedlings require a long period to mature before they are robust enough to transplant and produce usable stalks. Starting from seed may require three to four months before the plant reaches a harvestable size.
Conversely, propagating from a root division or a store-bought stalk is the fastest path to establishment. A fresh stalk placed in water can develop roots within one to three weeks, quickly transitioning into a developing plant. This method bypasses the lengthy seedling phase, allowing the plant to focus immediately on producing new shoots and foliage, giving it a significant head start.
Measuring Growth Through Clump Expansion and Harvest
Lemongrass growth is measured both vertically and horizontally through tillering—the continuous sending up of new shoots from the base. This process forms a dense, expanding clump of stalks. In warm climates, a well-established clump can expand its diameter by six to twelve inches annually, sometimes up to three feet.
The health and speed of growth are indicated by the density and diameter of this clump. Usable stalks must reach a diameter of at least half an inch at the base. Harvesting is best achieved by selecting individual, mature, outer stems, which encourages the plant to continue producing new shoots from the center.