The two types of light—direct sunlight and indirect sunlight—are the first topic we’ll cover in our indoor plant light guide. Both of these types of light are probably present in your home; the trick is to arrange your houseplants to take advantage of each type of light.
Direct Sunlight
Direct sunlight is defined as light that travels in a direct line from the sun to the plant. For instance, the majority of window sills receive direct sunshine. If your house doesn’t receive enough direct sunshine to feed your plant collection, you can also create direct light with LED grow lights.
Indirect Sunlight
When something blocks the sun’s path and diffuses or filters the light before it reaches your plants, this is known as indirect sunlight. Sheer curtains, furniture, a tree outside your window, or even a different indoor plant placed in front to shield the lower-light plant are some examples.
What qualifies as radiant indirect sunlight?
For plants, what is bright indirect light? The term “bright indirect light” refers to when the sun’s rays bounce off an object before reaching your plant. Plants will cast hazy, illegible shadows in direct, bright light. 800-2000 foot candles are the approximate amount of bright indirect light.
How can indirect lighting be created for plants?
In conclusion, brilliant indirect light is bright enough to read by and to cast a shadow, though not a dark, distinct one. It can be found a few feet away from south- or west-facing windows that are not sheltered, as well as close to windows that face north and east. Additionally, it can be produced by placing plants on windows that receive direct sunlight and diffusing sheer white curtains—the kind you can see through—between the glass panes.
In rooms or corridors without windows or if plants are placed in corners more than 5 feet from windows, bright adequate light for houseplants is probably not going to be present. You can use fluorescent or LED grow lights to produce bright, indirect light for such locations.
The best way to create bright, indirect light for your plants is by using your windows and the direction of the sun throughout the day.
Your windows’ orientation and how clear they are of obstructions both affect how much light your plants receive. Remember that white walls will reflect more light to your plants than dark ones.
South-facing window: Place plants that demand bright, indirect light about 3 to 5 feet away from the window or far enough back that the sun’s rays never quite reach them if your south-facing window receives a lot of sun during the day and is not shaded by surrounding trees or buildings. You can set your plants as close to that window as you like, as long as the sheer drape stays between them and the glass, if that window is shaded or covered with a sheer curtain that diffuses light.
West-facing window: The same general guidelines that apply to unobstructed south-facing windows also apply to unobstructed west-facing windows, especially those that face southwest. It often receives midday sunshine that is hotter and brighter than that coming through an east-facing window. You should therefore situate your plants 3 to 5 feet away from the window panes in these westward-pointing windows as well, or arrange a sheer screen between them and the window.
Unshaded east-facing windows receive direct morning sunshine, but the morning sun’s rays are softer than those of the afternoon sun. Therefore, a diffusing drape is not necessary when placing most plants that like bright, indirect light near or even on the ledge of an east-facing window.
North-facing window: Because north-facing windows rarely get direct sunlight, you may normally put plants that love bright, indirect light on their windowsills, where they will get the most light that is available there. You could want to put a mirror opposite the window to reflect more of the light back at the plants because even that might not be enough illumination for them, especially during the winter. As an alternative, think about getting an LED or fluorescent grow light.
How is indirect sunlight determined?
Interior plant lighting comes in three primary categories:
- Bright Light: A sunny window that receives direct light all day long is one that faces the south or west. It needs at least five to six hours of direct sunlight each day, ideally more. Avoid the temptation to relocate your plant closer to the window during the winter months when caring for plants can often be more difficult. The majority of plants that require lots of light won’t be able to withstand the chilly drafts that get worse the closer you get to a window.
- Indirect Light: The interior of a room that receives full light from a south or west-facing window will have indirect light. It can also have indirect light in areas with an east-facing window. This may also imply, for example, that there is a sheer curtain between the light source and your plant.
- Low Light: Especially in the winter, a lot of spaces meet this criteria. Low-light conditions include spaces that have windows that face north or that are partially shaded. If it’s difficult for you to read a newspaper, the lighting is usually poor. Even in dimly lit spaces, plants can still grow with the use of artificial lighting.
Is light coming in through a window regarded as direct sunlight?
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What does it actually mean when a houseplant needs direct sunlight while another needs indirect? We wanted to know if the plants we were growing in “direct light” were indeed receiving the necessary amount of sunlight. Here is what we discovered.
Is light coming in through a window regarded as direct sunlight? It varies. Direct sunlight is when the sun is shining directly on the plants, such as via a south-facing window. Indirect light is what is produced when the sun is shining brightly but doesn’t reach the plant directly.
When working with indoor plants, the distinctions between direct and indirect sunlight might be a little unclear. Let’s examine light’s behavior more closely as it passes through windows.
Is shade the same as infrared light?
Identifying direct and indirect sunlight outside is relatively simple. Simply compare the areas of your lawn that receive sunlight vs those that receive shade.
Because the sun’s rays are not shining directly on the plant, the majority of light inside is regarded as indirect light. However, there are various intensities of indirect light, from dim to intense.
What Is Direct Light for Plants?
The sun’s rays reach the plant directly when they are unimpeded. This only typically happens indoors when the plant is situated next to a glass door or on a ledge.
Indoor gardening is not possible for any plants that demand “full daylight” or extended periods of direct sunlight.
A single, black shadow will be cast in the direction that the light is coming from when the sun is directly on a plant.
Is Direct Light Bad for Plants?
Direct sunlight sometimes gets a bad rap in the world of houseplants, but it’s not necessarily the bad guy. The majority of houseplants can thrive without direct light and don’t even require it to grow.
Some plants, especially those that prefer the gentler morning sun, can endure very little direct light.
Crotons, snake plants, and succulents are a few species of houseplants that not only endure but also benefit from direct sunlight.
These are some of the plants you can put in areas of your home when direct sunlight cannot be avoided.
Is Morning Sun Direct Sunlight?
Direct sunlight is regarded as occurring in the morning. Even yet, it usually doesn’t feel as harsh as the midday sun.
For indoor plants that want more sunshine to blossom but are unable to withstand intense direct sunlight, this is a fantastic lighting solution.
What Is Indirect Light for Plants?
Ambient lighting is similar to indirect light. The plant is not in the dark, but neither are the rays directly contacting it.
Most rooms with windows have indirect lighting. To provide indirect illumination, a thin curtain can be draped over windows that get direct sunlight.
Low light and partial/full shade plants often thrive in these lighting conditions.
What Does Indirect Light Look Like?
Your plant’s leaves won’t be immediately exposed to the sun’s beams. Instead, general lighting is created in the space as a result of light reflecting off other things.
You might see several faint shadows projected in various directions rather than just one dark one.
What Counts as Bright Indirect Light?
Since brightness cannot be measured, it might be challenging for plant owners to figure out how much light is required to produce “bright, indirect light.”
First, the light must be indirect, which means that the plant must not be exposed to any direct sunlight. Bright refers to a higher level or intensity of ambient light.
The indirect light that is the brightest will typically be near a window or glass door. In comparison to low light, you will frequently notice darker shadows in bright light.
How To Measure Light Levels for Plants
There are a few techniques you may employ to more accurately describe the quantity of light in your home if you’re still unsure about the lighting levels in each room.
While some approaches are more scientific than others, they all ought to help you understand how your home is lit.
Shadow Test
Hold up your plant or your hand during the brightest part of the day (typically around noon) and look at the shadow that results:
One or two somewhat black shadows with slightly blurred edges appear in a bright light.
You can repeat the shadow test throughout the day based on how much light your plant requires (because the sun’s movement will result in varying light levels).
You can identify which plants will thrive in a particular environment if the bulk of the tests fall into a particular category of light.
When deciding a plant to house in that position, keep in mind whether you receive different categories throughout the day.
Light Meter
Buy a light meter or download an app to your smartphone to geek out on the estimated amount of light a location is receiving.
By using a light meter, you can count foot-candles (an outdated measure of illuminationone unit equals the illumination of one candle at a 1-foot distance).
The unit of measurement for your light meter can also be lux, or one-tenth of a foot-candle.
Even when you are using a light meter app indoors, make sure to turn the app’s outdoor measurement setting and point the camera at the light source (window).
You will expose the sensor and point it in the direction of the light source for a real light meter. You may calculate the light level there based on the reading:
- Low, indirect light is between 25 and 100 foot candles (ftc).
- Medium, indirect light, 100-500 ftc
- High, indirect light, 500–1000 ftc.
- Direct sunshine, 1000+ ftc
I would suggest this rapid-response type with a lighted LCD and spinning sensor so you only need to point in the direction you wish to measure for the most accurate readings.
Plant Growth/Appearance
Trial and error must be used to determine this light measurement. Place a plant where you think it will receive bright, indirect light if it is advised for that location.
Depending on the plant’s rate of growth, it may take weeks or months before any negative consequences of improper lighting become apparent.
Here are some indicators that the plant needs more light:
- growing quickly in the direction of the light.
- scant or leggy growth
- no fresh growth
- tiny leaves
- The soil is not drying up.
- losing diversity
- dark green foliage
Here are some indicators that the plant needs less light:
- Crispy, dry leaves
- patches of sunburn.
- brown borders
- foliage with a light color.
Many of these symptoms might also be brought on by pests, illness, or an unbalanced water supply. When experimenting with light settings, be sure all other facets of plant care are handled properly.
Which Direction Gets the Most Light?
The most light will enter a window facing south if you live in the Northern Hemisphere. This is due to the sun’s constant proximity to the equator.
Throughout the day, the sun also swings from east to west, so such areas will mostly receive morning or afternoon sun.
Indirect Light vs. Shade
Despite the fact that the phrases are frequently used differently, shade and indirect light refer to the same phenomenon.
In the outdoors, shade refers to a region where the sun doesn’t beam directly. This is typically close to a structure or shade-producing trees.
When sunlight does not directly touch a plant indoors, the lighting is referred to as indirect light.
Technically, due to the roof above and the surrounding walls, every indoor space is regarded as shaded (with the exception of areas where direct sunlight enters through a window).
Some plants may be grown either indoors or outside, so if you want to try growing them as houseplants, check for outdoor plants designated as “shade.”
What Is Partial Sunlight?
Three to six hours a day of direct sunshine is considered partial sunlight. In open spaces, this is simpler to accomplish.
However, it can also be done indoors in windows with a west, south, or east orientation.
The lighting here might not be ideal for them, though. The plant might not flower or develop to its full potential as a result.
Is Light Through a Window Considered Direct Sunlight?
It is technically not 100% direct sunlight when it shines through a window since some of it is refracted and veiled.
True direct sunlight, when the sun shines directly on the plant without any obstructions, can only be obtained outdoors.
However, direct sunlight is referred to when referring to indoor plants because it comes through a window.
This is so because this type of indoor light is the most direct and bright one available.
Direct sunlight from the outside or via a window may be too strong for houseplants because they do best in filtered or indirect lighting situations.
If sunlight enters a window directly, a thin curtain can reduce the brightness of the light, making it indirect.
North-Facing Windows
North-facing windows rarely receive direct sunshine in the Northern Hemisphere. In other words, they usually make a bright, indirect lighting atmosphere that lasts the entire day.
South-Facing Windows
South-facing windows will benefit sun-loving plants the most because they normally receive the most direct sunlight throughout the day (in the Northern Hemisphere).
East-Facing Windows
East-facing windows will receive direct sunlight in the morning, when the light is generally less harsh on sensitive plants and less intense.
For indoor plants that need plenty of sunlight to blossom but can’t stand too much harsh, direct light, this is an excellent place.