Rosemary will flower every year as a natural part of its life cycle. At least that is how it is supposed to be, so if your rosemary is not flowering, it could be because something is wrong and needs to be fixed. Luckily, that isn’t always the case, though.
I have written this article to help you identify and solve any potential problems and to clear up any confusion about why your rosemary might not be flowering.
With that said, let’s get into my list of the possible reasons why your rosemary isn’t flowering.
If your rosemary has been flowering but the flowers are dying and falling off, it is usually not a problem, although it can be a symptom of an underlying issue that you have to take care of. In that case, head over to this article about why rosemary flowers are dying.
With that said, here are the most likely reasons for rosemary not flowering.
Insufficient Sunlight (Should Be 8 Hours or More per Day)
Rosemary is native to the Mediterranean region which means it is used to full sun in high amounts, especially in the spring and summer. It should ideally get at least 8 hours of direct sunlight per day on average to thrive but more than that can promote growth and boost flowering even further.
The amount of sunlight a rosemary plant gets affects almost everything about how it grows including flowering but also the production and growth of new and existing foliage. In short, sunlight is the key to keeping rosemary happy.
So if your rosemary doesn’t get the sunlight it needs, that might explain why it isn’t flowering.
To solve the problem, see if you can find another location for it where it gets more direct sunlight. If you grow it in a pot, simply move the pot but if you grow it in the ground, consider taking a look at my guide on how to move established rosemary plants since that’s more complicated.
In my experience, lack of sunlight is often the cause of various problems when growing rosemary indoors. So if you’re doing that, consider moving it outside if possible.
Incorrect Soil (Should Be Sandy and Well-Draining)
The wrong type of soil will have a huge negative effect on how well rosemary grows and flowers.
Rosemary grows best in well-draining, sandy soil without much organic matter.
Too much organic matter can cause the soil to retain moisture too well. Rosemary needs to grow in soil where the water drains relatively quickly and easily, as it can otherwise lead to root rot and other moisture-related problems.
Additionally, soil with too much organic matter becomes too nutrient-rich for rosemary, which can lead to root damage and fertilizer burn.
If your rosemary is not flowering, consider taking a close look at the soil to see if it is the right type.
I have made the mistake of growing rosemary in soil with a high content of clay before. Clay retains moisture exceptionally well which is the exact opposite of what you want for rosemary. Not only did that plant never flower, but it barely lived for long enough to flower at all.
I tried getting a photo to show more or less how the soil should look and while it wasn’t easy to get a good photo, you can (kind of) see it here. Notice how light and sandy the soil looks. Light-colored soil is typically low in nutrients and as you can see, the plant in the photo is thriving.
Wrong Time of the Year (Usually Flowers in Spring or Summer)
Just because your rosemary isn’t flowering, it doesn’t mean anything is wrong. It could simply be because it isn’t the right time of the year.
It is most common for rosemary to flower in the spring or summer. However, it varies from region to region and based on growing conditions. In certain tropical and subtropical regions, rosemary can flower throughout the whole year.
So while rosemary USUALLY flowers in the spring or summer, it isn’t always the case. You can learn more about this in another article where I go into more detail about when rosemary flowers in different parts of the world.
This is especially true if you grow it indoors as the (more or less) consistent temperatures and limited sunlight can confuse the plant. I have a small, indoor-growing rosemary plant flowering right now at the time of writing this and it is the middle of December.
Too Much Nitrogen in the Soil or Fertilizer
While rosemary generally responds well to fertilizers with nitrogen, you should be careful not to over-fertilize as it can negatively impact growth and flowering.
When it comes to flowering, you have to be extra cautious with nitrogen. Nitrogen is excellent for the production of foliage but it can be at the expense of flowers.
So if your rosemary isn’t flowering, I recommend getting a soil test kit to see if the nitrogen content in the soil is too high.
Other than negatively impacting flowering, over-fertilizing can lead to root damage and fertilizer burn of the foliage, so it is crucial to avoid it.
Incorrect or No Pruning (Should Be Done Every Year)
While rosemary can grow fine without ever being pruned, there are many reasons to do it. One of the most important reasons is that it promotes the growth of new foliage and flowers.
When you prune your rosemary, you cut the stems (I have a whole guide on how to prune rosemary if you need some tips), which causes them to split and grow as two or more instead of the one that was removed.
More stems leave room for a lot more flowers, so if flowering is your goal, make sure you prune correctly.
It is best to prune rosemary one time per year and it is best to do so in the spring. That way, the temperatures are high enough so that the plant won’t become damaged from being cut while still leaving as much time as possible for it to grow before next winter.
Harvesting has the same effect but only if you do it correctly. I have seen many people just pick leaves one by one or strip entire stems of leaves. Instead of doing that, cut the stems entirely like I do in this photo as it will cause the stems to split.
Rosemary Rarely Flowers in the First Year
A very common reason why people’s rosemary might not be flowering when they expect it to is that the plant is too young.
Rosemary rarely flowers in its first year in most parts of the world. It is significantly more likely to happen in tropical and subtropical regions than in the rest of the world since it can get much more direct sunlight all year round in those parts of the world.
So if your rosemary isn’t flowering, consider if it is just too young. If it is still in its first year, all you can do might be to have patience and take good care of it until next year.
So in short, flowering happens as a natural part of the plant’s annual cycle but before it can happen, the plant needs to be mature enough. If you want to learn more, check out my article about why rosemary flowers and what it means.
Insufficient or Too Much Watering
Incorrect watering of rosemary can lead to many different problems, a lack of flowers being one of them.
While you shouldn’t underwater your rosemary, overwatering is a much more common problem. Rosemary can tolerate drought much better than many other herbs but is also more at risk of becoming overwatered. Especially if the plant is still young.
Both underwatering and overwatering will lead to several problems in rosemary and can negatively impact flowering.
To reduce the risk of incorrect watering, allow the soil to almost dry out completely between waterings. It shouldn’t dry out completely, but it should be close. Allow at least the top of the soil to become dry.
Pests and Diseases
Depending on your experience as a gardener, you might have had to deal with various pests and diseases in and on your plants.
Various pests and diseases can lead to various problems, not flowering being one of them. If the plant is busy fighting off pests or diseases, it might not have excess energy for the growth and production of flowers and foliage.
If parts of your rosemary seem to be infected, consider removing that part of the plant entirely to prevent the problem from spreading. If the entire plant seems to be infected, make sure to isolate it from your other plants.
Learn more about rosemary flowering
If you want to learn more about why flowering is important for rosemary, what happens to the plant, what you should do when your rosemary is flowering, and much more, head over to my complete guide to rosemary flowering where I cover absolutely everything about the topic.