Lavender’s distinctive, calming fragrance makes it one of the most popular herbs to cultivate and preserve. The aromatic quality comes from volatile organic compounds, known as essential oils, concentrated within the flower’s tiny glandular hairs, or trichomes. To capture the maximum scent for use in sachets, culinary applications, or decoration, precise timing and technique during harvest and drying are necessary. Controlling the preservation environment ensures the dried herb retains its potency and vibrant color for many months.
Determining the Optimal Time for Harvesting
The concentration of essential oils within the lavender flower spike peaks at a specific stage of bloom, determining the optimal harvest window. This ideal time occurs when the flower buds are fully colored, yet only about one-third to one-half of the individual florets on the stem have begun to open. Harvesting at this point ensures the highest concentration of fragrant compounds before they start to dissipate.
If the lavender is cut too late, when most flowers are fully open, the volatile oils begin to evaporate, and the color of the dried buds fades quickly. Conversely, harvesting too early means the essential oil content has not fully developed, resulting in a less potent final product. Monitoring for this visual cue—colored buds with only a few open flowers—is the most reliable method for achieving maximum fragrance.
Essential Cutting Techniques
The best time of day to harvest is in the late morning, after the morning dew has completely evaporated from the flowers. Harvesting a dry plant is important because residual moisture can lead to mold development during the drying process. Cutting before the intense heat of midday also helps, as the essential oils are most concentrated when temperatures are cooler.
Always use clean, sharp pruning shears or scissors to make a precise cut, minimizing damage to the stem tissue. The cut should be made to take the longest possible stem, just above a set of leaves or new growth nodes on the green, non-woody part of the stem. Making the cut at this point encourages the plant to produce new flower stems for a potential second flush of blooms later in the season.
Preparing Lavender for Preservation
Immediately after cutting the stems, prepare them quickly to facilitate efficient drying and prevent mold. Begin by inspecting the cut stems and gently shaking them to dislodge any small insects or debris. This immediate cleaning step ensures that only high-quality plant material proceeds to preservation.
Next, remove the small, grayish-green leaves from the bottom third of each stem to improve airflow within the drying bundle. Removing this excess foliage allows moisture to escape more rapidly. Finally, gather the stems into small bundles, ideally containing 10 to 15 stems, and secure them tightly just below the flower heads using a rubber band or twine. Smaller bundles are crucial for proper air circulation, ensuring uniform drying and fragrance retention.
Air-Drying Methods and Storage
Air-Drying Environment
Air-drying is the preferred method for preserving lavender, as it slowly removes moisture while maintaining the integrity of the essential oils. The ideal drying environment must be dark, dry, and well-ventilated, such as an attic or empty pantry, with temperatures between 60 and 70 degrees Fahrenheit. Darkness is necessary to prevent ultraviolet light from degrading the vibrant color of the flowers and reducing the potency of the aromatic compounds.
Drying Process
Hang the small bundles upside down from a hook or beam, ensuring adequate space between each bundle for continuous air movement. Hanging the lavender upside down helps the stems dry straight and directs essential oils downward into the flower heads. The drying process typically takes between two and four weeks, depending on the humidity level.
The lavender is fully dry when the stems snap easily when bent, and the flower buds feel crisp and crumble readily. Once completely dry, the flower buds, which hold the most fragrance, should be carefully stripped from the dried stems into a container. This process, called “stripping” or “threshing,” separates the potent buds from the woody material.
Storage
Long-term preservation requires proper storage conditions to protect the volatile oils from degradation. Store the stripped lavender buds in an airtight container, such as a glass jar or metal tin, to prevent the escape of aromatic vapors. The container should be kept in a cool, dark location away from sources of heat, light, and humidity, which cause the scent to diminish over time.