Pruning rosemary plants and bushes are necessary at least once a year to make sure the plant is kept healthy, lives longer, and is formed in a nice shape. If you don’t prune rosemary regularly, the plant will eventually get woody, will produce fewer leaves and flowers.
In this article, I will give you some pruning tips for your rosemary plant or bush so that it can stay fragrant, healthy, and beautiful in your garden or backyard for many years to come. I will cover when and how to prune rosemary, where exactly to make a cut, and which tools to use for the best results.
How to Prune Rosemary
First, let’s start by looking at how rosemary actually grows which helps with deciding where exactly to prune it. On the photo/ diagram below is a sample stem that I cut from my bush.
In the photo, you can see the growing blossom tip where the blossom forms. Further down the stem, there are small, needle-like leaves and small branches growing off the green stem. Towards the bottom of the stem, on the left side of the photo, there is a part of the branch that has become bare and woody with no leaves left.
If you trim or cut back at this woody part that cut will not stimulate new growth and will just leave a bare stem only. If you cut off the tip or make a cut further down on the green stem you will stimulate new growth as well as branching, making your rosemary more rounded and fuller.
The best pruning cuts are shown in the below photo – they are trims just above these last few green leaves leaving enough green living stem to produce new branches right above the cut.
How Much to Prune Rosemary
Basically, there are two kinds of pruning cuts – light and hard prune. The purpose of light prune is just to remove the tips of the stems after the blue blossoms fade. This cut spruces up your bush and promotes more blooming throughout the growing season.
So, if your intention is to promote growth, cut back your rosemary after flowering just a few centimeters below as in the above photo. Aim to maintain the size of the plant/bush through summer with light pruning as well as harvesting.
The second kind of pruning is a harder prune which is done annually. A hard prune is made every year, after the blooming season, to maintain the size and shape you desire. Hard pruning rosemary also promotes new bushy growth.
Cut off about 15 to 25 cm on green growing stems making sure not to cut into any bare wood and leave plenty of green leaves below your cut especially if you prune overgrown rosemary.
Work your way around your rosemary until you’ve removed about a quarter to a third of the plant. Also, remove the whole damaged or woody branches all the way down to the base of the plant.
If you would like your plants to create a hedge or large rosemary bushes, prune it regularly for few years, allowing each year to grow higher by about 25 cm.
When is the best time to prune rosemary
When should rosemary be pruned? You need to light prune your rosemary in the early spring, immediately after winter freeze to encourage growth. The second light pruning should be in early summer after the blossom fades to remove the blossom and possibly encourage the second blossom. And the third, hard pruning one, in late fall to shape and maintain the size of the plant.
Pruning Rosemary In Pot
Young Plant in Pot – You should start with rosemary pruning when your plant is very young and has no woody stems, as soon as you get it from a nursery. Just make a few cuts of longer stems to shape the plant the way you want. These light cuts will encourage new branches to form on the sides. Repeat that light cut for each one of the stems to shape and get even more side branches. Within a few months, your plant will become bushy, with numerous tips for blossoms and clips to harvest.
Well established plant in a pot – Once your rosemary is well established, do light and hard pruning the same way as explained above. These two kinds of pruning will help it to thrive even in small pots.
Pruning Woody Rosemary
If you have to deal with rosemary that is very woody, or mostly woody inside, the best option is to replace it with the young plant as it is very unlikely that you can encourage the growth from the woody parts. You can try pruning it very hard up to the last two sets of leaves above the woody part and see if it recovers. I never succeeded with my plants so I usually just replace them with young plants that I grow from cuttings.
The basic tool for light pruning is garden scissors or pruning shears. Good tools for this heavier pruning job are clean sharp pruners loppers, preferably, more efficient, bypass loppers, as well as a pruning saw.
Pruning rosemary bush with a hedge trimmer is also doable just be careful not to cut too much of the plant.
In this video, I am pruning my four years old rosemary bush Rosmarinus officinalis (Rosemary), which I grew from cuttings and planted next to my stone-built, off-grid cottage – have a look:
What happens if you don’t prune rosemary?
If you don’t prune rosemary at least once a year, and if it is grown freely planted in the soil, it can get pretty tall (up to 2 meters) and will get woody, will grow irregularly, and will look shabby. That’s why regular pruning is important to avoid bushes going woody and looking unsightly. Pruning rosemary regularly is an essential part of looking after the plant to stop it from getting woody.
Pruning rosemary plants and bushes are essential to do at least once a year to make sure the plant is healthy and good-looking. Keep your rosemary young with annual trimming/pruning, a regular bit of a cut back in order to promote new growth.