Pruning Lavender
When and how — Lavandula angustifolia
Prune your lavender in March, April and August — the optimal month is usually April.
The next pruning window is August.
When to prune?
The shrub lavender is pruned in March, April and August.
Sub-shrubs need a light prune — never into bare old wood.
Lavender, sage, rosemary, thyme and cotton lavender are technically shrubs, but they behave like sub-shrubs: only the bottom 10–20 cm becomes truly woody; above that, soft new growth appears each year. The golden rule: prune right after flowering, back to just above the green wood — never deeper into the bare base. There are no dormant buds left there, so nothing will regrow. A light prune twice a year (late August after flowering, plus a short shaping cut in March) keeps the plant compact and stops it from splitting open from the centre.
How to prune lavender
Lavender needs pruning twice a year to stay compact, floriferous and long-lived. Without it, plants become woody, bare at the base and prone to splitting open in wind or snow. The first prune is a light tidy in August, immediately after the main flowering flush. Use clean, sharp secateurs or garden shears to cut off all the spent flower stems, taking them back to just above the first set of leaves below the faded blooms. This deadheading prevents the plant wasting energy on seed and often encourages a modest second flush of flowers in early autumn. The main structural prune happens in March or April, just as new green shoots begin to appear at the base of the old stems. Cut back all the previous year's growth by about one-third to one-half, shaping the plant into a neat, rounded mound. Always cut into the green, leafy growth—never back into thick, bare brown wood, because lavender rarely regenerates from old stems and you risk killing whole branches or even the entire plant. If you're uncertain, err on the side of caution and take less off; you can always prune again next year. Use sharp bypass secateurs for precision or hedging shears for larger plantings and long hedges. Work your way around the plant evenly to maintain a balanced shape. If your lavender has become very leggy or woody, it's usually better to replace it than attempt drastic renovation. Well-pruned lavender will remain productive and attractive for ten to fifteen years.
Common mistakes
✗ Cutting back into the old, bare wood
The classic mistake with lavender and rosemary. The bare wood at the base has no dormant buds — nothing will regrow there. The plant goes bald on that side and never recovers. Always prune to just above the first green leaves.
✗ Not pruning at all
Without annual pruning a lavender breaks open from the centre after 4–5 years. Better to remove 20–30% each year than try a drastic cut every few years — most won't survive that.
✗ Pruning just before or during frost
Fresh wounds freeze easily and the plant can die back. Prune lavender in late August after flowering, or in March once the worst frost has passed — never in November/December.
Hold off on pruning
Better to wait than prune at the wrong moment. The next optimal window is August. Until then: leave the plant alone — only remove dead or diseased wood (which you can do year-round).
