Can Basil Get Too Much Sun? (Or Too Little?)

Basil thrives in the summer when it can get direct sunlight. It is commonly known that basil needs a lot of sunlight to thrive, but can basil actually get too much sun?

It is limited how much direct sunlight basil can get before it begins to take damage. As a general rule, basil should get between 6-8 hours of direct sunlight per day but it depends on the intensity of the sun. In spring and fall, basil can get more sun than in the summer.

Keep reading to learn how much direct sunlight is too much for your basil and what some of the signs that your basil is getting too much sun are.

Can Basil Get Too Much Sun?

There are several things you can optimize to grow the best basil but one of the most important conditions for basil to thrive and reach its full potential is direct sunlight, but can it be too much?

If basil gets too much sun it will begin to wilt and the leaves will begin to turn yellow or brown. Basil generally needs 6-8 hours of direct sunlight but can often benefit from more in the spring or fall when the sun is less intense than in the summer.

On the longest and warmest summer days, when the sun is up and shines on your garden or through your window for the entire day, it is important to keep an eye on your basil.

The first sign that your basil is getting too much sun is that the leaves will begin to turn yellow or even brown and dry out. In addition to that, the plant will start to wilt which is a mechanism plants use to reduce the amount of sunlight it absorbs.

Wilting essentially means that the leaves begin to droop and hang much looser than usual. They will become soft and begin the fold to reduce the overall surface area and thereby reduce the amount of direct sunlight that reaches them.

If the sun is too intense and hits basil for too long, it can cause the upper leaves to be scorched and become dark and dry. Young plants are more fragile than older plants and are more likely to take severe damage from being exposed to too intense sunlight for too long.

To prevent this issue, I recommend that you move your basil out of direct sunlight in the afternoon when the sun is most intense and then back to its original place after a few hours (more on that here).

Basil has thin leaves that do not contain as much water as many other plants’ leaves so when basil is exposed to direct sunlight for too long, the water in the leaves will evaporate faster than the plant can obtain water from the soil and the plant will begin to wilt to reduce the amount of sun it absorbs.

How much direct sunlight your basil should get also depends on where you grow it.

If you are growing basil indoors by a window, it can get more direct sunlight than if you are growing it in a greenhouse. This is because the temperatures in greenhouses can get much higher than indoors and since the glass in greenhouses rarely has UV-filtering which most glass used for windows do.

How do You Know if Your Basil is Getting too Much Sun?

Getting too much sun is a common issue when growing basil but luckily it is quite easy to see when your plant needs a break from the warm sun.

Basil leaves begin to turn yellow or brown when the plant is getting too much sun. Shortly after that, the plant will begin to wilt which makes the leaves fold. Plants do this to decrease the surface area of their leaves which reduces the amount of sunlight they absorb.

The photo above shows a basil plant I had a while ago that had been getting too much direct sunlight. Notice how the lower leaves especially are starting to fold and change color. On the bottom left, you can even see a few spots where the leaves got scorched a bit.

If basil is exposed to very intense direct sunlight for an extended period of time, the leaves can get scorched and turn brown and dry. Once this happens, the affected leaves do not recover and should be removed.

What Happens if Basil Does Not Get enough Sun?

If basil plants do not get enough sun, they adjust by growing slower and producing fewer, smaller leaves to better match the amount of energy they can absorb from the sunlight. In addition to that, the plants will stretch and become leggy in an attempt to reach a height where they can receive more sunlight.

Basil plants are excellent at adjusting their growth to the specific conditions they are given and the more direct sunlight they receive (up to those 6-7 hours), the faster they grow and the more leaves they will produce.

The reason for this is that the leaves are what allow the plants to absorb energy from the sunlight and if there is a lot of direct sunlight, basil will adjust by producing more leaves to get the most out of the sunlight.

If basil does not get enough sunlight, however, it acts completely opposite.

The photo above is a perfect example of how it looks when basil is getting too little sun compared to how it looks when it gets enough.

Both plants in the photo are my own and while they are both young, it is already easy to see that the plant on the right has been growing in more sunlight than the plant on the left since the leaves are much denser and not placed nearly as far apart as they are on the left plant.

The two plants were growing in different places so I solved the issue by just moving the left plant which had become stretched and leggy to the same place as the other plant which was doing great all along.

As you can also see in the photo, the small shoots that grow out near the main leaves are barely visible on the left plant. That is also to reduce the amount of energy the plant needs because it has not been getting enough direct sunlight.

Another thing you should know if you have a basil plant that is not getting as much sunlight as it might like is that it does not need as much water so the risk of accidentally overwatering it is higher.

The reason why basil plants that do not get enough direct sunlight are easier to overwater is that since they do not grow as fast and produce as many leaves to absorb sunlight, they are not able to use the water as fast so it stays in the soil for longer which can cause root rot.

I have written a post specifically about how to know if your basil has been overwatered and another one about how to save basil if it has been overwatered that you can take a look at if that applies to you.

Anders

My name is Anders, and I am the owner and writer here at Gardening Break. Gardening has always been a big part of my life. As a child, I would watch and learn as my parents worked in our garden or as my grandfather worked in his greenhouse. As I have gotten older, gardening has become a bigger and bigger part of my life. I have grown to enjoy it more and more, but I am also starting to realize just how much there is to learn about gardening, which is why I created Gardening Break in the first place; To share all the useful tips and tricks I learn along the way. You can read more about me and my mission with Gardening Break by following the "About Us"-link at the top and bottom of every page.

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