You may have heard that you should prune your rosemary before the winter and while there are cases where it can be done, the vast majority of us probably shouldn’t. I wrote this article to clear up the confusion and help you figure out precisely what you should do in your specific situation.
Rosemary can be pruned until 4-6 weeks before the first expected frost in the fall or winter although it is better to do in the spring after it finishes flowering. Rosemary should not be pruned in the winter unless it grows in a warm area with no risk of frost.
I already knew this before I wrote this article but since I wanted to go the extra mile and share some useful tips, I reached out to an acquaintance of mine. A fellow gardener who is highly educated in horticulture and who has been growing rosemary for many years. He gave me some excellent tricks that I share with you in this article.
Pruning Rosemary Before Winter: Why It’s Usually a Bad Idea
Pruning rosemary before the winter is optional. Pruning in the spring is generally best but it can also be done in the fall, although it must happen at least 4-6 weeks before the first expected frost. If done later than that, the plant might not have time to adapt and the frost might damage it.
Rosemary can technically grow and thrive without ever being pruned, so pruning is never really urgent but if you don’t do it, it will become tall and scraggly instead of bushy. This also means it won’t be as productive if you don’t prune it.
So assuming that your goal is to have a nice, bushy, and productive rosemary plant, you should definitely prune it. This isn’t the only reason why I think it is important though. I cover the importance of pruning rosemary here.
But I recommend doing it in the spring instead of in the fall before the winter. That way, the plant has as much time as possible to produce new foliage that will be strong enough to make it through the winter.
That said, you can prune your rosemary before the winter if that’s what you prefer, for example, if you’re going to be too busy in the spring. Just make sure you do it no later than 4-6 weeks before the first expected frost.
Pruning too late is a common mistake that can potentially kill your rosemary in severe cases. It is far from the only one though. I cover more common mistakes when pruning rosemary here.
What do I personally do?
I always prune my rosemary in the spring. Ideally just after it finishes flowering. That’s what I have seen the best results from, so I also recommend that you do that.
The exception is for growth that is turning yellow or brown and dying. I always remove that right away regardless of what time of the year it is and I recommend you do it too since it brings several benefits and can lead to issues if you don’t. I go into more detail about that in another article where I, of course, also explain the best way to remove dead foliage from your rosemary.
I go into more detail about why spring is the best time to prune rosemary now.
Why Spring Is the Best Time to Prune Rosemary
Rosemary can be pruned at any time from about 3 weeks after the last frost in the spring or late winter until 4-6 weeks before the first frost in the fall or early winter. If you have the option to choose, one specific time of the year is better than the rest, though.
Spring is the best time of the year to prune rosemary. It is ideally done right after the plant finishes flowering but can be done already from 3 weeks after the last frost.
The primary reason why spring is the best time is that it gives the plant as much time as possible to regrow and produce new foliage. This new foliage also has as much time as possible to grow and become stronger, which gives it the best chance of making it through the next winter.
I have written another article where I go into more detail about this and cover more reasons why spring is the best time to prune rosemary.
If you prune just before the winter, the new foliage is more fragile than if you did it in the spring since it doesn’t have nearly as much time to become strong. This means that there is a much higher risk that the plant will become damaged from the cold weather.
Pruning at the right time of the year isn’t the only thing you can do to help your rosemary make it through the winter. I share a couple of simple but effective tricks for that now.
If you have decided that it is time to prune your rosemary, I recommend reading my full guide on how to prune rosemary where I share absolutely everything you should know to get the best results.
4 Simple Tips for Keeping Rosemary Alive Over the Winter
Rosemary can tolerate light frost which gives it a much higher chance of surviving winters than many other herbs, but it is, unfortunately, far from invincible.
That’s why I wanted to include these four tips that can help it make it through the winter.
Do not prune or harvest more rosemary in the winter than you need
As I already covered in this article, you shouldn’t prune rosemary in the winter but light harvesting is different.
You can harvest from your rosemary all year round as long as it is not colder than 10-20° F (about -7 to -12° C) but rosemary almost always dies if it gets that cold.
Just make sure you only harvest what you need during the cold months, though, because rosemary is a lot more fragile at cold temperatures than during the rest of the year. If you want to learn more about this, I have written another article where I cover the topic of pruning rosemary in cold months.
If you want to harvest a lot of rosemary at the same time, wait until the spring and do it as part of the annual pruning. The milder weather and gradually increasing temperatures make it much easier for the plant to adapt
Cover your rosemary with a plant cover in the winter
A very easy way to give your rosemary a better chance to survive a cold winter is to cover it with a plant cover. It is an easy and inexpensive way to protect it from the most extreme temperatures.
I talked to an extremely experienced and knowledgeable gardener from a local garden center about this one time. He told me that if you happen to have a bunch of spruce branches, they can be used as an excellent plant cover for rosemary. He often did that to protect his rosemary in the winter.
Move potted rosemary indoors or near the house in the winter
If you grow your rosemary in a pot or container, it can benefit greatly from being moved closer to the house or even inside in the winter.
Most houses are not perfectly isolated and give off a bit of heat. Your rosemary can benefit from this by being near the house and that way be better protected from extreme cold. If you have the room, you could even move the plant indoors until spring.
If your rosemary is growing in the ground, a raised bed, or a pot that is so large or heavy that you can’t move it, I recommend looking into plant covers as I mentioned above.
Only water rosemary in the winter if there has been no rain for two weeks
This is more of a general rule since the specific amount of time you should wait before watering in the winter depends on the growing conditions your rosemary has. If it looks too dry, give it some water even if it hasn’t been two weeks.
The reason why you should be careful with watering rosemary too much in the winter is that it already doesn’t need much water and since there aren’t high temperatures or much sunlight at that time of the year, the water stays in the soil for longer without drying out.