When to prune rosemary – for fuller and healthier plants, fast

Knowing when to prune rosemary is one of the simplest but most effective ways to improve your plant's health and keep pests away. But why does this time frame matter?

While you may have mastered how to grow rosemary (and how to harvest rosemary for delicious aroma and flavor in cooking or floral displays), it is equally important to know when to begin the pruning process. Though, the time frame is refreshingly generous – stretching across many months of the year.  

This is when the experts prune rosemary – for healthy, fragrant shrubs that will continue to look good for longer. 

When to prune rosemary

'Rosemary is quite unpretentious when it comes to pruning, so you can do it anytime starting from spring and up until four to six weeks before the first frost hits,' says Bryan McKenzie, a garden expert and co-founder of the Bumper Crop Times. 

The expert explains that rosemary is best pruned in warmer weather, as it becomes weaker in cool temperatures. 'If you choose to prune it during cold seasons, your rosemary bush won't be able to harden off as its new growth will become too tender and sensitive to temperature,' he says. 

Melody Estes, a Landscape Design Gardening Supervisor from Maine and a consultant at The Project Girl, agrees. She, too, urges you to cut in the month before you expect the first frost, and also warns against pruning in wintertime. 

'Rosemary is a perennial herb that can be grown indoors or out. It's best to prune rosemary when the plant is in active growth and in full sun. Pruning will encourage new growth, making your plant fuller, bushier, and more attractive,' she says.

How often should you trim rosemary?

Rosemary needs to be trimmed regularly, especially if you plan on harvesting the leaves or flowers. Melody suggests cutting just before it blooms, but this can depend on whether it's a bush type or a tree form of rosemary.

'If you have a bush-type rosemary plant, you should prune the branches back in spring just after they've bloomed. This will encourage new growth at the base of the plant and help keep it looking full and healthy throughout the growing season,' the expert says. 

Meanwhile, if you're working with a bush rosemary plant, it is better to remove any new shoots that appear on older branches – to allow the branches to keep producing flowers and leaves throughout the summer months (or longer). 

FAQs

The process behind how to prune rosemary is one of the easiest (but most rewarding kitchen garden ideas) you can follow. 'Cut off any shoots that are growing straight up and down, as they will not produce flowers or buds later on in spring,' says Melody Estes. 'Prune off any branches that have grown larger than 2 inches in diameter. This helps ensure your plant stays healthy and does not become too large for its space.'