If you grow rosemary in your garden on your window sill you will already know how powerful and punchy little super herb it is.
The drought-tolerant plant, Salvia rosmarius, originally comes from the Meditteranean and is an evergreen shrub that grows small and delicate silvery green leaves. If left to flower rosemary blooms pretty and petite blue flowers.
Not only is rosemary aromatic and fragrant added to roast lamb and poultry, crunchy roast potatoes, stews and soups. The hero herb is antioxidant-packed and full of anti-inflammatory compounds to boost health and well-being.
'Rosemary can grow quite well in the UK climate, although it does need extra shelter during the winter. The rosemary plant requires full sunspots outside, well-drained soil, and shelter from wind. It can tolerate temperatures down to -6°C,' says the Director of Polhill Garden Centre, Josh Novell.
When to prune rosemary
Knowing when to prune rosemary properly will avoid herb garden mistakes and ensure your shrub remains healthy. Being a perennial plant, pruning rosemary will continue to provide you with a delicious crop, if planned and executed correctly.
It's important not to get rosemary pruning confused with rosemary harvesting. The Royal Horticultural Society (RHS) states that Rosemary is evergreen, so can be harvested all year round, but the soft new growth in summer has the best flavour. Snip off any shoots as required, aiming to keep an attractive shape to the plant.
Pruning rosemary is necessary to ensure the popular garden herb keeps its shape, delay stems from turning spindly or woody and continues to produce a healthy harvest.
The best time to prune rosemary is during late spring. This gives new growth time to establish itself before winter returns.
'Rosemary is one of the most reliable Mediterranean plants we can also grow in the UK. Prune Rosemary when the spring growth has shot up to keep it in shape. Keep some of the cuttings to grow new plants. Free plants are one of the great benefits of learning when to prune,' explains sustainable gardener, Melanie Hick.
Wait until the plants have finished flowering for best results.
How to prune rosemary
What you'll need
Established growing rosemary
A container to collect clippings
Once you know when to prune rosemary and that time of year arrives, start by preparing your tools.
'Prune shears or small sharp scissors are best for pruning rosemary, as they provide control and precision. Make sure that your tools are sterilised with rubbing alcohol before use, especially if you’ve used them recently on other plants,' advises Josh Novell.
'Make sure the shears haven’t gone blunt when tackling the thicker branches. The sharper the better when handling stubborn stems. Always remember to wear suitable garden gloves to ensure you’re protected from any potential injuries,' agrees Chris Bonnett at GardeningExpress.co.uk.
Next, check the shrub for dead or damaged branches.
'Prune away any dead or damaged branches with your pruning shears. Be sure to remove all of the brown parts, as these could encourage disease in the plant. Deadhead spent or faded flowers damaged or diseased shoots, and low-lying branches that touch the ground. Cut back to the first set of green leaves or to a main stem,' says Josh Novell.
'Cut away any overgrown growth that has become too dense and is blocking airflow around the plant. It’s important to keep the overall shape of the shrub in mind when pruning, as over-pruning can result in a less attractive-looking rosemary plant.' Continues Josh.
Like Rosemary's Mediterranean cousin lavender, avoid cutting back stems too close to the wood as the plant will never recover and you will need to buy a new shrub or propagate a fresh batch.
'If you want to make your rosemary plant look fuller, reduce the cutting to around one and a half inches so the branches start the splitting process and create a thicker appearance,' adds Chris Bonnett.
Why should you prune rosemary?
Pruning rosemary is important for encouraging the production of new growth. It is essential if you want your rosemary bush to keep its shape and not go leggy. Plus pruning will also help your plant work up the best flavour for cooking.
How big can rosemary grow?
There are many types of rosemary species that range from ornamental miniature plugs to hardy shrubs that can be grown as border bushes. If you know how to cut back lavender the outcome is the same: left unpruned rosemary can become wood, leggy and bare at the base whatever the herb size.
Does rosemary attract pests?
According to the RHS, rosemary has few problems with pests. Two main contenders can cause issues. These are, Scale insects, which can weaken growth and lead to black sooty mould on the leaves and Rosemary beetles. Both the larvae and adults eat rosemary leaves.