Rosemary Getting Leggy — How to Prune It Back Into Shape

A rosemary plant left to its own devices will naturally grow into a sprawling, woody shrub with bare lower stems and a crown of green at the top. This "leggy" growth habit makes the plant harder to harvest, less visually attractive, and eventually reduces the amount of fresh growth you get. The good news is that a few well-timed cuts each year keeps rosemary compact and productive for a decade or more.

Why Rosemary Goes Leggy

Rosemary naturally becomes woody as it matures. The lower stems lose their leaves as the plant directs energy upward to new growth. Without pruning, you end up with bare brown stems at the base and a bush that sits well above head height in a few years. Low light accelerates this: a rosemary that does not get at least six hours of sun per day stretches upward in search of light, producing long, weak stems with sparse foliage.

When to Prune Rosemary

The best time to prune rosemary is immediately after it flowers in spring. This allows you to enjoy the blooms — which are attractive and edible — and still gives the plant the whole growing season to put out new bushy growth before winter. A light trim in late summer is also beneficial. Avoid cutting back into old wood after midsummer, as the plant needs time to harden new growth before the first frosts arrive.

How Far Back Can You Cut?

Rosemary will not regrow from old, brown wood the way that lavender can occasionally manage. Never cut back further than the last green leaves on any stem — if you cut into bare brown wood, that stem will not regenerate. This is an important rule that many gardeners learn the hard way. Work stem by stem, cutting each one back by one-third to one-half, always to just above a leaf node where you can see green growth.

Shaping a Neglected Plant

If your rosemary has been neglected for years and is very leggy, do not try to restore it in one cut. Instead, prune it back gradually over two to three seasons — taking about a third of the overgrown stems each year. This gives the remaining stems time to produce new lateral shoots and prevents the plant going into shock from a sudden drastic reduction. Feed with a balanced fertiliser in spring to support new growth after each session.

Preventing Legginess in the First Place

Regular, light harvesting throughout the growing season naturally keeps rosemary bushy. Every time you cut a sprig for cooking, cut just above a leaf node and rotate around the plant rather than always cutting from one side. This encourages branching and keeps the shape compact. Grow rosemary in full sun and in well-drained soil — plants stressed by shade or poor drainage always grow more leggy than those in ideal conditions.