Lavender is a fragrant, semi-woody shrub prized for its aromatic foliage and vibrant purple flowers. This perennial is hardy and long-lived, but its structure requires intervention to remain healthy and productive. Without regular shaping, lavender plants quickly become leggy, woody, and produce fewer blooms. Proper pruning is the most important maintenance step to ensure the plant maintains a dense, compact form and flowers abundantly each season.
The Primary Annual Pruning: Timing for Rejuvenation
The most substantial pruning of the year is performed to rejuvenate the plant and prevent the development of a sparse, woody base. The ideal timing for this major cut occurs in late winter or early spring, just as the first signs of new, green growth emerge. This timing allows the plant to heal quickly and focus energy on vigorous shoot production before the main flowering season. This annual shaping is typically a hard cut, removing approximately one-third of the plant’s total height and width.
Cutting back deeply encourages branching lower on the stem, maintaining the desirable mounded shape of the shrub. In warmer climates, this deep cut can also be performed immediately after the first large flush of blooms finishes in late spring or early summer. This post-flowering timing allows the plant to spend the rest of the growing season recovering. Observing the appearance of new leaves is a helpful cue, ensuring you are cutting into active growth rather than dormant wood.
Maintenance Trimming After Flowering
The second, lighter pruning is a maintenance trimming performed in mid-to-late summer after the first major bloom cycle concludes. This action, frequently referred to as deadheading, involves removing the spent flower spikes and a small amount of upper foliage. The goal is to tidy the plant’s appearance and encourage a potential second, though usually smaller, flush of blooms later in the season.
This light maintenance cut removes only the top few inches of green growth, preserving the overall shape. For continuously blooming varieties, such as some French types, this frequent trimming helps redirect the plant’s energy from seed production to creating new flower buds. Removing the faded flower heads maintains a cleaner look and keeps the foliage dense and healthy throughout the summer.
Variety-Specific Timing Considerations
The specific species of lavender determines the optimal timing and intensity of cuts. Hardier English Lavender (Lavandula angustifolia) and its hybrids (Lavandula x intermedia) tolerate the deepest cuts, and their primary rejuvenation pruning is most often done in early spring or late summer. If pruning in late summer or early fall, complete the task at least six weeks before the first expected frost to allow the cuts to heal.
In contrast, the less cold-hardy Spanish Lavender (Lavandula stoechas) and French Lavender (Lavandula dentata) have different requirements due to their earlier and continuous bloom cycles. These varieties should only receive gentle shaping after their first bloom, avoiding deep cuts into their older, established structure. A hard cut in the fall is risky, as they lack the resilience to survive winter without sufficient green foliage. These varieties benefit from frequent, light deadheading throughout the blooming period, rather than one major annual cut.
Essential Technique: Avoiding Cuts into Old Wood
Understanding the structure of the lavender plant is necessary for successful pruning, especially the distinction between new growth and “old wood.” Old wood is the gray, hard, leafless stem material found at the base of the plant. This material is prone to splitting and does not readily regenerate new growth buds.
The rule of lavender pruning is to never cut into this old, woody section, as the plant rarely recovers and may die back entirely. When performing the annual rejuvenation cut, always aim to leave at least two sets of healthy, green leaves or new shoots on each stem above the woody base. Using sharp, clean shears or secateurs is advisable to make precise cuts, which minimizes trauma and promotes faster healing. This technique ensures the plant retains the necessary vegetative material to sprout new, vigorous stems.