As a lavender plant, we are sun-worshipping, woody-stemmed perennials. Our natural form is a dense, rounded mound, but without your careful intervention, we become "leggy." This is not an aesthetic preference but a survival strategy. Our lower, older stems naturally lignify (turn to wood) to support new growth. Without pruning, we stretch for light, energy becomes focused on the very tips, and the base becomes a bare, woody skeleton, weak and unable to produce the fragrant foliage and blooms we are known for. Pruning is the human action that mimics the beneficial grazing of wild herbivores, encouraging us to regenerate from lower down and maintain our vitality.
From our perspective, this is the most vital rule. Our old, brown, woody stems have dormant buds, but they are reluctant to sprout. If you cut back into this non-productive wood, you risk creating a permanent bald spot or, worse, the entire stem may fail to generate new growth and die back. Our life and foliage come from the younger, green-grey, flexible stems. The goal of your pruning is to encourage new growth from these points, not to shock the ancient, foundational wood.
Your timing is crucial for our recovery. We have two primary windows for pruning. The first and most significant is after our main flowering, typically in mid to late summer. You deadhead the spent flower stalks and, at the same time, give the foliage a light shaping cut. This directs our energy away from seed production and into strengthening our core structure before winter. The second, more aggressive pruning happens in early spring, just as you see tiny new green buds swelling at the base of our stems. This is the signal that we are actively pushing new growth, and it is the safest time for a harder cut to correct legginess without causing winter damage.
For a lavender that has become overgrown, a two-stage approach over two years is safest for us.
Year One - The Spring "Rescue": In early spring, locate the point on each leggy stem where you see a small, green shoot or a pair of leaves. Using sharp, clean shears, make your cut approximately one to two inches above this growth node. Do not cut back by more than one-third of the plant's total height in this first session. This may still leave us looking somewhat sparse, but it forces energy to those lower buds, initiating the first wave of new, lower growth.
Year Two - Establishing the New Shape: By the following spring, the new growth from the previous year will have established itself. Now, you can perform a more standard pruning. Again, in early spring, you can cut back the entire plant, including the new growth from last year, by about one-third. Aim to create that desirable rounded mound shape. This second cut will further encourage density and finally restore our compact, beautiful form.
Once our shape is restored, consistent annual pruning will prevent a return to a leggy state. Each year, after flowering, give us a light trim to remove the flower spikes and shape the foliage. Then, the following early spring, before new growth accelerates, give us a more decisive pruning, cutting back by about one-third, but always ensuring you are leaving some green leaves on every stem. This consistent practice maintains our dense, leafy base and ensures we remain a vibrant and floriferous part of your garden for years to come.
