Lavender, a highly aromatic herbaceous perennial, is prized for its striking color and distinctive fragrance. While propagation through vegetative cuttings is the most reliable method, growing lavender from seed offers a cost-effective alternative. Starting lavender from seed presents challenges, mainly due to inconsistent germination rates and the need to break dormancy. Success requires carefully mimicking the plant’s native Mediterranean environment before sowing.
Preparing Lavender Seeds for Sowing
Before planting, lavender seeds require cold stratification to simulate natural winter conditions. This period of cold and moisture breaks the seed’s internal dormancy and softens the hard outer coat, significantly increasing successful sprouting. Without this treatment, germination rates are low and erratic.
To stratify, place the seeds in a small container or plastic bag with a slightly damp medium, such as fine sand, peat moss, or a moist paper towel. Seal the container and place it in a refrigerator, maintaining 35°F to 40°F (2°C to 4°C). This chilling period should last four to six weeks. Check the medium weekly to ensure it remains lightly damp and to prevent mold development.
Once stratification concludes, sow the seeds into a sterile, well-draining seed-starting mix. This specialized mix, often a blend of peat moss, perlite, and vermiculite, is preferred over garden soil because it is lighter, provides better aeration, and reduces the risk of fungal diseases. Transitioning the seeds from the cold refrigerator to a warmer environment signals the end of “winter” and encourages germination.
Sowing Technique and Optimal Depth
The primary factor for successful lavender germination is ensuring the seeds receive sufficient light, which dictates the planting depth. Lavender seeds require light for germination, meaning they cannot be buried deeply. Planting them too deep is the most common reason for failure, as the seeds remain dormant without light exposure.
The optimal strategy is to surface-sow the seeds, gently pressing them onto the prepared, moistened seed-starting mix. If a covering is used, it must be extremely minimal, consisting of only a fine dusting of material. The recommended maximum depth is approximately 1/8 of an inch (about 3 millimeters), achieved using fine vermiculite, grit, or a thin layer of sifted sand. This light covering maintains contact with the moist soil while allowing light to penetrate.
When planting in a seed tray, space the seeds about half an inch apart to allow for proper air circulation and growth. Use a clean toothpick or tweezers to accurately place the tiny seeds on the surface. After sowing, lightly mist the surface with water to settle the covering material without dislodging or burying the seeds deeper than intended.
Maintaining Conditions for Successful Sprouting
After sowing, the environment must be managed to promote sprouting. A consistently warm soil temperature is required, ideally maintained between 65°F and 75°F (18°C to 24°C). Gardeners often use a heating mat beneath the seed tray to reliably achieve this optimal warmth, which accelerates germination.
The planted seeds require bright light for 12 to 16 hours daily. While a sunny window may suffice, supplemental light from a fluorescent or LED grow light positioned a few inches above the tray is highly effective. This light exposure, combined with the warmth, triggers the final stages of germination initiated by cold stratification.
Consistent moisture is equally important; the seed-starting mix should remain uniformly damp but never waterlogged, which promotes fungal growth. Misting the surface with a spray bottle is the best way to water gently without disrupting the shallow planting. Sprouting typically occurs within two to four weeks, though some varieties may take longer. Once seedlings emerge, remove any humidity dome and increase air circulation to strengthen the young plants and prevent disease.