Lavender, a fragrant Mediterranean shrub, requires regular attention to maintain its dense, mounded shape and ensure continuous purple blooms. Pruning is not merely a cosmetic task but a necessary practice to prevent the plant from becoming woody, leggy, and sparse over time. Properly timed cuts stimulate new, leafy growth that is more floriferous, extending the plant’s productive life. In California’s varied climates, knowing precisely when to prune is the most important factor for success.
The Critical Late Winter Pruning
The most substantial pruning of the year should occur in late winter or very early spring, before the plant begins its active growth cycle. This heavy cut rejuvenates the shrub, removes old material, and establishes the plant’s framework for the coming season. The ideal timing is after the last threat of hard frost has passed but before any significant new green shoots have emerged.
In many parts of California, this window falls between late January and mid-March, depending on the specific microclimate. This annual deep cut removes dead or damaged wood that may have suffered during the cooler months and encourages a flush of strong, healthy new growth from the base, which will be the source of the season’s flowers.
The late winter prune is the deepest cut the plant receives all year. Cutting back the previous season’s growth prevents the plant from allocating energy to old, woody stems that produce fewer blooms. This practice ensures the lavender remains compact and productive.
Maintenance Pruning After the First Bloom
The second, lighter pruning occurs immediately after the main flush of flowers has faded, typically in mid-to-late spring or early summer. For many varieties, this timing falls around late May or June. This cut, often called deadheading or shearing, serves a distinct purpose from the winter prune.
This maintenance cut prevents the plant from expending energy on setting seed, which diverts resources away from vegetative growth. Removing the spent flower stalks and the top few inches of foliage encourages a second, smaller bloom cycle later in the season. The cut should be light, only removing the flower spikes and the soft, green growth immediately below them.
Shearing the plant at this time helps maintain a tidy, rounded shape throughout the summer. This lighter pruning is focused on shaping the plant and promoting repeat flowering, making it less aggressive than the winter cut. This lighter pruning is especially important for varieties that are known to re-bloom throughout the growing season.
Essential Pruning Techniques for Lavender Health
Regardless of the season, pruning lavender must adhere to a fundamental rule: never cut into the gray, leafless, old wood. Lavender plants do not reliably regenerate from this woody tissue, and cutting into it can lead to the plant’s decline or death. Always make the cut into the green, leafy portion of the stem, ensuring there is visible foliage below the cut point.
For the heavy late winter cut, remove approximately one-third of the plant’s total green growth from the previous year. This substantial reduction stimulates branching and maintains the plant’s compact, mounded form. Always use clean, sharp pruning shears to make precise cuts, which helps the plant heal quickly and reduces the risk of disease.
To achieve the desired rounded shape, prune the outer stems slightly shorter than the central stems. This technique allows light and air to reach the interior of the plant, preventing the center from becoming too dense and woody. Consistent, annual pruning into the green growth is the best way to prevent the formation of bare, unproductive old wood.
Adapting Timing to California Varieties and Microclimates
California’s mild, Mediterranean climate means different lavender species may have varied pruning schedules compared to colder regions. English lavender (Lavandula angustifolia) generally adheres to the standard two-cut annual schedule: a hard cut in late winter and a light trim after the first bloom. Its main flowering occurs in late spring to early summer.
However, varieties like Spanish (L. stoechas) and French (L. dentata) lavender thrive in California’s heat and often have a longer, sometimes continuous, blooming period. These varieties may require more frequent, lighter trims throughout the growing season, especially in coastal areas. Rather than a single heavy cut, they benefit from a continuous cycle of deadheading and light shearing after each flush of flowers.
Coastal regions experience a milder winter, meaning the late winter cut can sometimes be delayed until late February or early March. Conversely, inland valleys and high desert areas have more distinct seasons and should adhere more strictly to late January or early February timing. Observing the plant’s new green growth, regardless of the calendar date, remains the most reliable indicator for the optimal time to prune.