Even though it is not a requirement, rosemary can benefit greatly from being pruned but only if you do it right. If you prune your rosemary when it shouldn’t be pruned, it will do more harm than good, which is why I wrote this article. I want to teach you how to know if your rosemary should be pruned.
In this article, I cover seven signs that indicate that you should consider pruning your rosemary. Let’s get into it.
1. Dead or Dying Growth
One of the best reasons to prune rosemary is to clean it up and remove dead or dying foliage.
Removing dead growth can make a plant look more aesthetically pleasing but far more important than that is that it can reduce the risk of various problems and even encourage new growth.
When you prune away dead or dying foliage, the plant will divert its energy toward the production of new growth rather than toward recovery.
So make sure you prune your rosemary to remove dead growth. Especially if it looks like my plant in the photo above where it is starting to affect entire stems rather than individual leaves.
I have written another article where I go deeper into the topic of removing dead growth from rosemary. In the article, I cover the best way to do it, why it is important, and more.
2. Leggy and Scraggly Growth
Rosemary grows naturally in many parts of the world where nobody comes and prunes it and while it can grow and thrive without it, it becomes much bushier and more productive if you prune it. If you want your rosemary to become bushy and productive, you should prune it.
If your rosemary is leggy and scraggly like the one in the photo above, you should consider pruning it as it will encourage new growth and cause the plant to become much bushier and fresh-looking over time. It might take a couple of seasons since you shouldn’t prune more than 1-2 times per year, but it is definitely worth it.
I have another article where I go into detail about how often rosemary should be pruned, which I recommend reading if you’re not sure.
If you don’t already do it every year, you should prune your rosemary annually unless you don’t mind that it looks like the one above. It definitely has its charm but is highly inefficient if the goal is to harvest.
3. The Plant Has Become Dense or Overcrowded
You should consider pruning your rosemary if it has become too dense or overcrowded.
If your rosemary is too dense, it can inhibit proper air circulation. Limited air circulation can create humid conditions, which increases the risk of fungal diseases like powdery mildew. Consider thinning it out by cutting away some stems at the base.
If your rosemary has become overcrowded by growing too close to other plants, it might create competition for essential resources such as water, nutrients, and sunlight. This competition can lead to stunted growth and reduced overall plant health.
If this is the situation you’re in, you should definitely prune either the rosemary or the other plants to prevent them from staying too close. Head over to my full guide on how to prune rosemary to learn everything you need to know.
4. It Is Spring and the Plant has Just Finished Flowering
It is best to prune rosemary one time per year in the vast majority of the world with the exception of the warmest and sunniest places where the plant grows rapidly throughout most of the year. In those areas, pruning twice per year can be beneficial.
The best time to prune rosemary is in the spring right after it finishes flowering.
So if that’s the situation you’re in, you should definitely consider pruning your rosemary if you haven’t done it already.
Rosemary flowers are excellent for attracting bees and other pollinating insects, so if they still look like mine above, you should wait a bit longer before you prune your plant.
Once the flowers start to dry out, they won’t attract as many insects. That’s when you should ideally prune your plant.
I have another article where I go into more detail about the best time to prune rosemary that I recommend reading as it can really help optimize your plant’s productivity.
I took the photo above around the end of March but since growing conditions are different everywhere, your rosemary might flower earlier or later than mine. It usually happens in spring, though.
Once the flowers dry out and the seeds are brown, you can collect the seeds as you prune your plant if you wish.
5. The Plant Has Outgrown Its Location
Whether your rosemary’s roots have outgrown the pot or container your plant stays in or the plant itself and its foliage are becoming too large for its location, pruning can be a solution.
If you are growing rosemary in a pot or you bought a plant from a garden center or another store, there is a risk that it can become root bound. In my experience, rosemary is actually often root bound, or close to it, when you buy it. I got the one above from a garden center and this is how it looked from the beginning.
If your rosemary is root bound like mine in the photo above, consider pruning its roots to keep it thriving in its pot. If you want to learn more about how to do this and when it is a good idea, check out my complete guide to root pruning rosemary.
If the foliage on your rosemary is taking up too much space, you should probably prune it. Cut the plant back to a size you like but not by more than a third to prevent too much stress.
6. The Plant Has Not Been Pruned for Over a Year
While it is true that rosemary can tolerate infrequent pruning, pruning it every year is generally the optimal way to maximize its productivity.
Pruning less frequently than every year can lead to lower productivity, increase the risk of problems, and negatively impact the plant’s aesthetics.
The plant above hasn’t been pruned every year like the plant at the top of this article. The difference isn’t huge yet, but this plant has more woody parts and the foliage is darker and not as fresh as the one at the top of the article.
So if you haven’t pruned your rosemary for a few years, you should definitely do it as soon as possible. Just make sure you do it at the right time. Ideally spring, but it is fine to do until about 4-6 weeks before the first frost in the fall or winter.
I have another article in which I cover the topic of how often you should prune your rosemary.
7. Pruning for Aesthetic Reasons
People have very different opinions on how important aesthetics are in a garden but chances are you at least want a nice-looking rosemary bush. Pruning is a great way to achieve that.
If you care about the shape of your plant, want to keep it a certain size, or just want to trim away dead growth or growth you want to be removed, you should give your rosemary a good pruning every year.
Of course, you can prune in many different ways and while you shouldn’t give your rosemary a heavy pruning more than 1-2 times per year, you can more or less always give it a light pruning. Just make sure you allow it to grow back before pruning again.
Harvesting is also always fine and can be viewed as a light pruning.
Depending on how you want to shape your rosemary when you prune it for aesthetic reasons, you might need different tools. That’s why I wrote an article where I cover all the tools used for pruning rosemary and in which situations the different tools make sense to use.