Lavender is valued for its fragrance and purple blooms, offering a cost-effective way to cultivate large quantities from seed. While buying established plants guarantees immediate success, starting lavender from seed presents unique challenges. The long germination time and specific pre-treatment needs mean that simply tossing seeds into the soil is rarely the most effective approach.
Feasibility of Direct Sowing Lavender Seeds
It is technically possible to plant lavender seeds directly into the garden soil, as this is how the plant reproduces in nature. However, direct sowing is generally discouraged for gardeners seeking predictable results and a high success rate. The low yield is primarily due to the difficulty in maintaining the specific conditions required for successful germination outdoors.
Lavender seeds need consistent moisture and a precise soil temperature, typically around 70°F (21°C). This is difficult to manage outdoors due to weather fluctuations, competing weeds, and pests. Many lavender varieties also exhibit a natural dormancy that must be overcome before sprouting, making the process unreliable. While winter sowing provides the necessary cold, the resulting seedlings remain highly vulnerable to harsh conditions.
Essential Preparation Before Planting
To maximize successful germination, lavender seeds require cold stratification. This preparation mimics the natural exposure to cold, moist conditions experienced over winter, effectively breaking the seed’s dormancy. Skipping this step often results in sporadic and significantly reduced germination rates.
The most effective method is moist cold stratification in a refrigerator. Seeds are placed on a damp medium, such as a moist paper towel or seed-starting mix, and sealed in a plastic bag or container. Store this sealed container in a refrigerator, not a freezer, at 35–40°F (1.5–4.5°C) for 30 to 40 days. This cold, moist environment signals to the embryo that it is safe to begin growth.
Step-by-Step Guide to Starting Seeds Indoors
Starting lavender seeds indoors provides the necessary controlled environment for optimal germination. Begin the process approximately 8 to 12 weeks before the last expected frost date. Use shallow seed trays or containers filled with a sterile, well-draining seed-starting mix, which prevents compaction and root rot.
Lavender seeds are light-dependent germinators. Sprinkle the pre-treated seeds directly onto the surface of the moistened mix and press them gently to ensure contact. Cover them with only a very thin layer of fine sand or vermiculite, no deeper than 1/8 inch. The ideal soil temperature for germination is consistently warm, around 70°F (21°C), which is reliably achieved using a heating mat beneath the trays.
The seeds require ample light for 12 to 16 hours daily, best supplied by a dedicated grow light positioned just above the tray. The growing medium must be kept consistently moist but never waterlogged, as excess moisture encourages fungal issues like damping off. Using a spray bottle or bottom-watering technique helps maintain the necessary moisture without disturbing the seeds. Germination typically spans two to four weeks.
Moving Seedlings Outdoors and Site Selection
Once the lavender seedlings have developed several sets of true leaves and reached about three inches in height, they are ready to be gradually introduced to the outdoor environment. This transition process, known as hardening off, toughens the plants and prepares them for the harsher conditions of full sun, wind, and fluctuating temperatures.
Begin by placing the seedlings in a shaded, protected outdoor location for just two hours on the first day, bringing them back inside overnight. Each day, incrementally increase the exposure time and the amount of direct sunlight they receive, reducing the frequency of watering slightly to encourage sturdier growth. After the hardening process is complete and all danger of frost has passed, the young plants can be transplanted into their permanent outdoor location.
Lavender requires a site that offers full sun exposure for at least six to eight hours and exceptional drainage. The native soil should be amended with materials like sand, grit, or perlite to ensure water drains quickly. Planting lavender in a sunny, well-drained spot with adequate air circulation ensures the long-term health and survival of the plants.