Rosemary is known for its resilience and hardiness as it can withstand a lot. That includes pruning which you can do throughout most of the year in most parts of the world. If you want to get the best results, however, one specific time of the year is the best time to prune your rosemary.
The optimal time to prune rosemary is in the spring immediately after it finishes flowering as that gives it time to regrow before next winter. However, it is noteworthy that the pruning window lasts from three weeks after the last frost in the spring until four to six weeks before the first frost in the fall or winter.
Since not all rosemary bushes grow under the same conditions and flower at the same time, it is not possible to give you a specific date or month to prune yours, but I do have a handful of easy tricks you can use to figure it out.
Best Time of the Year to Prune Rosemary
The best time to prune rosemary depends on growing conditions and climate. Light pruning can be done throughout the whole year but a more comprehensive pruning should be done at the right time.
Here are some guidelines to determine the best time to prune YOUR rosemary.
Heavy pruning:
- Heavy pruning is ideally done in the spring three weeks after the last frost as that gives the plant the maximum amount of time to regrow before next winter.
- You can find historical weather data for your region online to see the average last frost date.
- If the timing allows it, prune your rosemary after it finishes flowering as that allows you to benefit from the bees and other pollinators the flowers attract.
Light pruning and harvesting:
- Can be done throughout the year. The only thing you need to keep in mind is that you don’t overdo it.
- I recommend harvesting evenly from different parts of the plant whenever you harvest. That way it has time to grow back properly and will keep a nice appearance.
If now is the time, you should check out my guide on how to prune rosemary to learn the best way to do it and a bunch of tricks that can make the task easier.
Even though spring is the best time for heavy pruning, you can actually prune your rosemary throughout the entire summer and usually well into the fall. Just make sure you do it no later than 4-6 weeks before the first expected frost.
I have often been asked if it is fine to harvest rosemary during the cold months or if you have to wait until it gets warmer and then harvest a lot and preserve it. You can definitely harvest a lot and preserve it but if you only need a little bit of fresh rosemary, it is absolutely fine to harvest throughout the whole year. If you want to learn more about this, I recommend reading another one of my articles about pruning and harvesting rosemary in cold months.
Cutting Rosemary Back for the Winter (Why It Is a Bad Idea)
Rosemary can be pruned lightly and harvested throughout the year including in the fall and winter but harder pruning is different.
A lot of people ask if they should cut their rosemary back for the winter and the answer is a clear NO.
As I covered earlier in this article, the pruning window for rosemary extends from spring to fall but once we get close to winter, heavy pruning should be avoided.
To be more specific, avoid pruning your rosemary extensively later than 4-6 weeks before the first expected frost.
I have another article where I go into detail about why you shouldn’t cut rosemary back for the winter, which you can read if you want more detail, but here are the most important reasons.
- Higher risk of pests and fungal infections since the plant doesn’t grow nearly as fast as normally and won’t recover from cuts nearly as fast.
- Increased risk of damage from the cold since the plant won’t recover from the open cuts as fast as in warmer weather.
- Reduced aesthetic appeal is of course a matter of opinion but since rosemary doesn’t regrow properly until spring, pruning it in late fall or winter can cause it to lose some of its aesthetic appeal.
If you need a bit of fresh rosemary, don’t hesitate to harvest a bit but don’t overdo it. I recommend that you only cut the tips off each stem like I do in this photo if possible since deeper cuts can cause problems when it is too cold. Of course, how much you can cut depends on the size of your plant, so if you have a large rosemary bush, you can cut more than this.
Pruning Rosemary in the Summer (Why It Is Not Ideal)
Before I get started about why summer isn’t the ideal time to prune rosemary, I want to emphasize that it is not wrong to do it in the summer. It is just not the optimal time. That would be spring.
I try to always prune my rosemary in the spring for the reasons I listed earlier in this article but I have also done it in the summer and while it still works fine, the differences were clear to me.
Here are some reasons why summer is not the optimal time to prune rosemary:
- Since rosemary is growing actively and spending most of its energy on producing new foliage in the summer, pruning can interrupt this period of active growth.
- Since pruning in the summer can interrupt the plant’s growth, it often leads to less vigorous and bushy plants that aren’t as productive as if they were pruned in the spring before the period of active growth started.
- Many rosemary varieties flower during the summer. Pruning during this period often involves removing the flowers and while that doesn’t cause significant damage to the plant, it means that fewer bees and other pollinators will visit your garden.
- Since rosemary can be sensitive to extreme heat, pruning in the summer can lead to damage as it exposes fresh cuts to intense sunlight and high temperatures. The plant is much better protected from this if it is pruned in the spring as it has time to recover before summer.
If you want to shape your rosemary during the summer, it is best to perform only light pruning. If you want to prune it extensively, I recommend waiting until next spring.
Always remove dead growth, regardless of the temperature and amount of sunlight, as it allows the plant to spend more energy on the production of new foliage rather than recovery. If you want to learn how to do this in the best and easiest way, I recommend reading my article about how to trim away dead growth from rosemary.
Best Time of the Day to Prune Rosemary (And Why It Matters)
One of the most important things when it comes to pruning rosemary is that you do it at the right time of the year. However, if you want to optimize it and give your plant the best conditions possible you should also know what time of the day is the best.
The best time of the day to prune rosemary is in the morning after the dew has dried but before the sun gets too hot. This minimizes stress on the plant and gives it the maximum amount of time with sunlight on the first day after being pruned, which helps it recover faster.
Plants are usually fully hydrated early in the morning which makes it the perfect time to prune as it can help reduce stress. This plus the fact that it is usually more humid in the morning helps reduce water loss from the parts that were cut.
Additionally, pruning in the morning means that the plant isn’t exposed to intense sunlight yet, which can help reduce the risk of sunburn.
While morning is the recommended time for pruning rosemary, it is important to note that light pruning and removal of a few leaves and stems can be done at any time.
Heavy pruning should ideally be done in the morning as it reduces the risk of stress and makes it easier for the plant to recover for the reasons I wrote above.
Timing isn’t the only way to know if your rosemary should be pruned. I cover some signs to look for now.
How to Tell if Rosemary Needs to Be Pruned (4 Signs)
If you’re new to growing rosemary, it can be difficult to tell if it should be pruned or not but luckily for you, I have been growing rosemary for many years so I know precisely what to look for and that’s what I want to teach you.
Here are some signs that it might be time to prune your rosemary.
- Leggy and scraggly growth
- Dead or dying foliage
- Dense and overcrowded foliage
- The plant has outgrown its location
I have to mention that while these can all be signs that you should prune your rosemary, they can also be symptoms of other things.
To figure out for sure, I recommend reading another one of my articles where I cover more signs and go into more detail about the signs that rosemary should be pruned.