Lavender is one of the most loved plants in gardens across the UK, admired for its fragrant blooms, silvery foliage and ability to attract bees and butterflies. Beyond its ornamental charm, lavender has been used for centuries in aromatherapy, medicine and cooking. Like many perennial plants, lavender requires regular pruning to stay healthy and attractive. One of the most common questions gardeners ask is when to cut back lavender plants. The timing of pruning is vital because it affects not only the plant’s appearance but also its longevity and flowering. Understanding when to prune lavender, how much to cut back and why pruning matters will help you enjoy strong, healthy plants for many years.
Why lavender needs pruning
Pruning is not simply about keeping a plant neat. For lavender, it is essential to its survival. Without regular cutting back, lavender plants quickly become woody and leggy, producing fewer flowers and losing their compact shape. Once lavender has turned to thick woody stems, it is very difficult to rejuvenate it. Regular pruning encourages fresh growth, maintains the rounded mound shape and stimulates more flower spikes. In essence, pruning lavender each year extends the life of the plant and improves its overall performance.
The best times of year to prune lavender
In the UK, lavender is typically pruned twice a year: once in late summer after flowering and again in early spring. The late summer prune is the most important, as it tidies up the plant after the blooming season and encourages new shoots to grow before winter. Early spring pruning is lighter, removing any damaged or dead growth that occurred over the colder months. These two pruning sessions ensure the plant remains healthy, vigorous and attractive throughout the year.
Late summer pruning
Late summer pruning should be carried out immediately after the main flush of flowers has faded, usually in August. Cutting back at this time prevents the plant from putting energy into seed production and instead channels it into root and shoot growth. This ensures that the lavender is strong enough to survive winter. The general advice is to cut back the flowering stems and trim the foliage to create a neat dome shape, avoiding cutting into old woody stems. Leaving some green growth ensures the plant can photosynthesise and recover.
Spring pruning
The second pruning is done in early spring, usually around March or April, depending on the region and climate. At this stage, gardeners should remove any dead or frost damaged stems to encourage fresh growth. This prune is much lighter than the late summer cut and helps prepare the plant for the flowering season ahead. Pruning in spring also allows you to shape the plant slightly if needed, maintaining its rounded appearance. However, cutting back too hard in spring can weaken the plant, so it is best to be gentle.
Why timing matters
Pruning lavender at the wrong time can have consequences. If pruning is delayed until autumn, particularly October or November, it can encourage new growth just as frosts are setting in. These tender shoots are vulnerable to cold damage, leaving the plant weakened. Similarly, leaving the plant unpruned through summer allows it to become leggy and woody, reducing its lifespan. Timing your pruning to late summer and early spring ensures that lavender is both resilient and productive.
The difference between English, French and Spanish lavender
The type of lavender you grow also influences pruning schedules. English lavender, which is the hardiest and most common in the UK, responds well to regular pruning and can live for many years if cared for properly. French and Spanish lavenders are less hardy and often shorter lived. They can be pruned in the same way, but more care must be taken not to cut them back too hard, as they are more prone to winter damage. In colder regions, French and Spanish lavenders benefit from being pruned more lightly and provided with protection during harsh winters.
How much to cut back
The golden rule with lavender is never to cut into the old woody stems, as these rarely sprout new growth. Instead, cut back about one third of the plant each year, focusing on the soft green stems. In late summer, cut back the spent flower stalks and trim foliage to maintain a dome shape. In spring, remove only what is necessary to clear dead growth. This careful approach prevents over pruning while still keeping the plant healthy.
Tools and techniques for pruning
Sharp secateurs or shears are the best tools for pruning lavender. Clean cuts reduce the risk of disease and help the plant heal more effectively. When pruning, aim for a rounded shape rather than leaving the plant flat on top. This dome like structure allows sunlight to reach all parts of the plant and promotes even growth. Shaping also prevents the centre from becoming too woody and hollow. For large lavender hedges, shears may be more efficient, but the same principles of avoiding woody cuts and maintaining shape apply.
Signs your lavender needs cutting back
If your lavender is becoming straggly, producing fewer flowers or showing bare woody patches at the base, it is a clear sign that it needs pruning. Healthy lavender should have dense foliage and abundant flowers. Neglected plants may still survive but will look unattractive and offer little fragrance. Once lavender becomes too woody, it is often best to replace it with new plants rather than attempt rejuvenation. This is why consistent pruning from the start is so important.
What happens if you do not prune lavender
Failing to prune lavender shortens its lifespan dramatically. Instead of lasting ten years or more, unpruned plants often become unmanageable and need replacing after just a few years. The centre becomes woody and bare, the flowers fewer, and the plant loses its compact shape. Neglecting pruning also reduces the aromatic oils in the leaves and flowers, meaning the plant becomes less fragrant. In short, unpruned lavender quickly declines both in beauty and function.
Conclusion
So, when should you cut back lavender plants? The answer is twice a year, with a main prune in late summer after flowering and a lighter tidy up in early spring. These timings ensure that lavender remains healthy, compact and productive, avoiding the problems of woody growth and weak flowering. English lavender responds well to this routine, while French and Spanish types require a gentler approach. With proper pruning at the right times, lavender will reward you with many years of fragrant blooms and vibrant foliage, enhancing your garden with both beauty and scent.
