When deciding where to position your houseplants, it’s always a good idea to first check how much light they need to thrive. But when you see that yours loves direct sunlight, this always prompts a question when it comes to indoor plants: what is direct sunlight, exactly, in this context? And is light through a window direct sunlight?
And for any plant that doesn’t need completely direct sunlight outdoors, you’re then faced with the next dilemma of which windows in your house still have enough light for your plant to thrive.
After all, making sure your houseplant’s light requirements are met is key for ensuring they’re able to thrive – but you also need to balance this out with the fact that too much light can cause issues.
Fortunately, it’s not so difficult to figure out. Take a look below to see exactly what counts as different types of light and how to figure out which parts of your home will work for this.
What is direct sunlight?
Direct sunlight is when light from the sun reaches the Earth or a specific object without being blocked or impeded by any obstacles. For gardening purposes, this is when sunlight directly falls on the plant without anything in the way creating shade, such as a sheer curtain or something more solid, like a tree, wall or roof.
When dealing with outdoor plants that like direct sunlight, the question is quite easy. That is, in most cases, either the plant is in shade or it’s not.
But indoors, the question of what is direct sunlight for plants can be a bit more nuanced beyond simply having a direct sunlight definition, especially when you’re dealing with things like the direction of windows. Learning the difference though is key to your houseplants’ health.
If the sun’s rays shine directly through the window and land on the plant’s leaves – this is direct sunlight. Most areas in your home, except for south-facing windows, receive indirect light.
Is light through a window considered direct sunlight?
Light through a window is not direct sunlight as the light will be filtered as it comes through the glass, which impacts its intensity. This means that this light can be at least 50% less intense than direct outdoor sunlight, although sunlight through a south-facing window can be close to direct light.
While some indoor settings can come close to providing direct light, such as large glass south-facing glass windows (in the northern hemisphere – look for north-facing windows in the southern hemisphere), any plant that thrives in direct sunlight is going to grow better outdoors.
What is indirect sunlight?
Indirect sunlight is any sunlight that passes through something before reaching the plant. This could include when light comes through glass or sheer curtains or even when it reflects off a surface. An area receiving indirect sunlight may not receive light throughout the entire day.
The exact meaning of direct sunlight vs indirect sunlight can be found by looking at what’s known as the “foot candles” of a certain light source. This can be really helpful to know when figuring out where to position your houseplant, as moving your plant from one window to another in your house could see your plant getting only around 5% of the light intensity it was getting before.
A lot of experts also set houseplant light requirements in “lux”. In fact, if you do have a number of indoor plants with different light needs, it can be a good idea to use a light meter, like this one, which measures in lux. That way, you can be absolutely sure that a chosen position is right for your plant.
What does indirect sunlight look like?
Indirect light will cast blurrier shadows with edges that aren’t as sharp as shadows formed by direct light. This is because, by definition, indirect light will pass through or bounce off something first. Seeing the shadow formed by your hand is a common way to test indirect light in an indoor area for your plants.
That said, bright indirect sunlight – like what may come through your south-facing window – can still feel quite strong with shadows that are still fairly well-defined. This means that it can be hard to simply look at the shadows that are formed by a particular light source to determine the exact intensity, so be careful not to over-expose your indoor plants and burn them.
How many foot candles is direct sunlight?
Direct sunlight indoors is considered as being in the range of 2,000 to 5,000 foot candles. Outdoors, direct sunlight is anything in excess of 4,000 foot candles.
The various foot candle and lux measurements are as follows:
|Direct sunlight outdoors||40,000-130,000 lux; 4,000+ foot candles|
|Direct sunlight indoors||20,000-50,000 lux; 2,000-5,000 foot candles|
|Bright, indirect light||10,000-20,000 lux; 1,000-2,000 foot candles|
|Low light||2,500-10,000 lux; 250-1,000 foot candles|
|Deep shade||500-2,500 lux, 50-250 foot candles|
What if the light through a window is too strong for your houseplants
There are a few things you can do to make sure your indoor plant isn’t burned if you’re worried that the light is too intense where you’ve positioned it. These include:
- Put up sheer curtains – Sheer curtains still allow some light to get through but filter out some of the intensity, allowing for softer light into the room while still ensuring your plant gets some of the light it needs. These don’t have to cost a lot, as proven by these very inexpensive sheer curtains that also look beautiful.
- Add a UV window tint – These reduce the intensity of the sun coming through a window and have the added bonus of being great for improving energy efficiency. I always recommend this UV-reducing window film as it applies with static rather than adhesive – perfect if you mess it up and need to try again.
- Move the plant a few feet away – As you can see from the table above, simply moving your plant out of, say, bright indirect light into medium light can reduce the light intensity by up to 94%. This could involve moving your plant to an entirely different room or simply moving it a few feet away from a window. Remember that if you want to be absolutely sure your plant’s light needs are being met, having a light meter can really help.
Do plants need direct sunlight or just light?
Plants have different light needs, with some preferring direct sunlight while others will burn and eventually die if placed in light that strong. In particular, although certain outdoor plants can often tolerate direct sunlight, many indoor plants will not. For houseplants, finding the right light level is critical for their overall health.
This is going to take some light (pun fully intended!) research on your side to see exactly how much light your specific plant likes. That, in turn, will help you see where in your house your plant should go.
For example, a houseplant that needs bright, indirect sunlight should go near a window where it gets enough light to be happy, but not too much light that could be considered as approaching direct sunlight. Too much light can burn your plant, but not enough light is also a problem, so finding the right balance is important.
Learn the signs that your plants are getting too much light to be on the lookout for any warning signs.
Can plants grow without direct sunlight?
Plants can certain grow without direct sunlight. In fact, many prefer indirect light, with direct sunlight being too strong for them leading to scorched leaves. The exact amount of light your plant prefers will, however, come down to the individual needs of that type of plant.
This is why it’s a good idea to do some research before bringing your new plant home. In particular, consider where you want to add a plant to your home, check the kind of light that this area receives and then confirm whether your intended plant prefers that type of light or would do better elsewhere.
For example, these low light hanging plants would be perfect for somewhere that doesn’t get much light at all.
How do you know if your plant is getting too much light?
If your plant is getting too much light, you will start to see brown, dry patches appear on the leaves or on their edges and tips. Leaves can also turn yellow, starting at the tips, and the plant will wilt. The soil may also start to dry out and, eventually, the plant will die.
When the soil is at the point of looking noticeably drier due to the light intensity being too strong, given that this is where your plant gets its moisture, be aware that this can speed up the process of your houseplant dehydrating.
If you notice any of these symptoms forming on your plant, move it a few feet away from the light source to ensure it’s still getting some light, but at a weaker level. You should also search the exact species of your plant to check its light needs, like if it’s a low light succulent, and figure out if there is a better, more permanent place in your home where it could live without getting sunburned.
Is a grow light considered direct sunlight?
A grow light is not considered direct sunlight as its intensity is not as strong as what a plant would receive if it were outside. It is, however, typically stronger than what a plant would receive through a window. A general rule is that 12 hours under a grow light is equivalent to around six hours of direct sunlight.
Adding, say, LED lights can help your plants grow, even those houseplants that don’t actually want direct sunlight. That is, even those plants that prefer indirect light can really benefit from a grow light if it’s not getting its light needs met by natural means. If you go down this route, it’s good to be aware of the “conversion rate” between the time your grow light should be on compared to how much natural sunlight that equates to, so you can adjust accordingly.
Related: What’s the Difference Between LED Lights and LED Grow Lights?
Is sunlight through a window good for plants?
Sunlight through a window can be good for plants as long as you keep in mind that its intensity is not as strong as direct sunlight outdoors. If a plant needs direct sunlight to thrive, sunlight through a window won’t be enough. Conversely, too much light through a window can be a bad thing for certain plants.
That is, on the question of whether it’s good for plants to get sunlight through a window, direct sunlight may be better depending on the needs of the plant. However, as a lot of problems with houseplants come from them not getting enough light, at least putting them as close as possible to a window will often solve many of these.
This is, as always, dependent on your specific type of plant though, as there are even indoor trees that prefer low light conditions. As such, make sure you check its individual light needs when deciding where to move it.
Is direct or indirect light better for plants?
While many outdoor plants can tolerate direct light, indirect light is often better for indoor plants. This is because plants that are typically used as houseplants tend to burn if exposed to direct light. That said, this is going to depend on your type of plant and its specific light needs.
There’s no hard and fast rule in terms of direct light vs indirect light, especially for indoor plants, even if bright indirect light tends to be the preference for many houseplants. I’d recommend doing a simple Google search on your type of plant to see what it prefers, so you can determine where to put it accordingly so it gets the best amount of light for its needs.
Which side of the house gets the most sun?
In the northern hemisphere, the south-facing side of the house will get the most sun. This means that if you have a houseplant that likes a lot of sun, try to place it near a south-facing window. In the southern hemisphere, this is reversed in that the north-facing side of the house will get more sun.
This means that the best house orientation for natural light is one where your home’s main living areas facing south (or north if you’re in the southern hemisphere).
So the exact window where you place your indoor plants can have a major impact on how much light they receive, as we’ll run through below.
(Just keep in mind that the comments below are assuming you’re in the northern hemisphere. If you’re in the southern hemisphere, each one can simply be reversed.)
Do south facing windows get direct sunlight?
While south-facing windows don’t get direct sunlight, as the glass filters out some of the light’s intensity, it is as close as you will get to direct sunlight indoors. This means that plants placed next to south-facing windows will generally receive the most light.
This also assumes that you don’t have anything like a sheer curtain blocking some of this light, as even something small like this can have a significant impact on the amount of light that gets to your plant.
Why do plants like south facing windows?
Certain plants like south-facing windows as it is the brightest light available indoors. This meaning that south-facing window plants receive the optimal levels of light for photosynthesis, helping them grow. That is, however, assuming that your plant prefers this amount of light, as some will actually thrive in less light.
In addition to checking the light needs of your specific houseplant, just be careful depending on where you live that your south-facing windows aren’t too hot, as your houseplant can get burnt even if it’s inside.
Do north facing windows get direct sunlight?
North-facing windows will not receive direct sunlight, so will result in a room being darker but more evenly lit with a cooler tone of light throughout. This means that plants placed near a north-facing window should not be varieties that need a lot of light to thrive.
Given that north-facing windows don’t get light that’s as bright as in other rooms, this means that, similarly, north-facing window plants won’t get as much light as they could elsewhere.
This isn’t necessarily a bad thing, as some plants do prefer indirect light – or even less, like these plants that can survive without sunlight.
How much sun does an east facing window get?
An east-facing window gets sun in the mornings, when the sunlight isn’t quite as intense. A room with an east-facing window will generally receive indirect light up to around five feet into the room, depending on the size of the window.
This means that east-facing window plants are those that enjoy some less intense light for a few hours a day. Houseplants for east-facing windows can include popular ones like the philodendron, monstera, pothos and spider plant.
Which direction window is best for plants?
Generally, south-facing windows are the best for plants as they receive the brightest sun throughout the day, giving them the ideal conditions for photosynthesis, helping them grow. However, plants that prefer sun that’s less intense may prefer a window in a different direction.
This means that it’s important to look up your plant’s light needs, which is usually going to be based on their natural environment, to determine the best position for your houseplant. While a south direction window gets the sun most of the time, this may not actually be preferable for every indoor plant.
As one example we just mentioned, plants that come from tropical rainforests but live below the main canopy will actually thrive more away from a south-facing window, as this will better replicate where they’re from.
How do you tell which way your window is facing?
A compass can tell you which way your window is facing. Alternatively, if your room receives sun all day, it’s probably south-facing. If it’s only in the morning, it’s an east-facing window and, if only in the afternoon, you have a west-facing window.
The easiest way for you to know which direction your window faces though is to simply use a compass, which comes preinstalled on most smart phones these days. If you don’t have it on yours, find a free app that does this – there’s no reason to pay.
Final thoughts on direct sunlight vs indirect sunlight
While you may not be able to get completely direct sunlight through a window, it should be pretty clear by now that the light needs of many houseplants can easily be met simply by being aware of where in your home you should put your plant.
Given that the light through a window isn’t direct sunlight, at least not in the strictest sense, any plants that need this would be best placed outside. However, for others, simply checking their light requirements in terms of foot-candles or lux will make it a very easy process for figuring out where they should go.
This will then let you see whether that south-facing window would be perfect or if that east- or west-facing window may have just the amount of light your indoor plant is looking for.