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.
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.
What does indirect lighting look like for plants?
Because the sun is not directly overhead the plant, it does not cast a precisely defined shadow, which is why a shadow that is feeble and has hazy or blurry edges suggests indirect light. Low light is indicated by a shadow that is hardly discernible. Although it is quite faint, there is still enough light to cast a shadow to some extent.
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.
Do windows count as indirect sunlight?
Indoor plants have a wide range of light needs, and many are especially sensitive to direct sunshine. But does sunlight that comes through a window count as direct sunlight? Let’s together research this.
Is light coming in through a window regarded as direct sunlight? Since some of the light is scattered and reflected as it goes through the window and lessens in intensity, light coming through a window is not always direct sunshine. The most direct source of light inside, light through a window, is typically at least 50% less bright than direct sunlight outside.
Your indoor plants need the correct amount of light to grow healthily, but you don’t want to overdo it to the point where they start to struggle. Discover how powerful light coming through a window actually is by reading on.
An illustration of indirect lighting
Sunlight that has been filtered via a surface or reflected off one before reaching your plants is known as indirect light. Since the Sun can only be on one side at once, the bulk of natural light in your home is actually indirect.
The process of hitting the surface reduces the intensity of the light beams to variable degrees, much like a wayward ball bouncing off (or going through) a window. Depending on the window’s characteristics and the force of the initial impact.
Examples of indirect light include general room illumination, light that is filtered via blinds or curtains, and light that is reflected off of surfaces like walls.
Direct Sunlight vs Indirect Sunlight
How do I recognize indirect lighting? It’s similar to recognizing a neutral odor, I suppose. Watching out for what it isn’t is simpler. As a result, I usually check for the telltale symptoms of direct sunlight before assuming it is indirect.
Do you:
- See distinct light beams entering your room through your window?
- Are there any obtrusive shadows cast by anything in front of the window?
- Do you feel the sun’s warmth on your skin?
How Does Terrarium Glass Affect Sunlight?
Has anyone actually discovered that glass terrariums intensify sunlight and potentially burn your plants, despite the widespread perception that this is the case?
Although it makes sense in theory, all the evidence I’ve found points to glass as having a significant light intensity reduction.
I can only imagine that it may be possible if your terrarium were designed to focus light. Curved glass terrariums can concentrate sunlight in specific regions that could put your plants at risk of scorching, just like a conventional magnifying glass.
I can’t say that I’ve tried it since I’m not sure whether I have the courage to. I’d appreciate it if someone with a background in physics could do the figures for me.
Plus, terrariums are still greenhouses and will still retain heat, so excessive sunlight exposure is still dangerous. Terrariums are at risk from direct light in a variety of ways, but it appears doubtful that they would be burned by light magnification.
Is light from an east-facing window indirect?
Some of our most gorgeous houseplants prefer the bright, indirect light that east-facing windows provide. Short bursts of morning sunlight, before it gets too hot, are provided by this exposure, followed by dappled light for the whole of the day. In the filtered sunlight of a forest canopy, many beautiful tropical plants developed and make ideal east facing window plants.
If you’re fortunate enough to be the owner of such priceless property, you can grow a variety of beautiful and popular plants that are otherwise picky about their lighting. 14 of the greatest plants for an eastern exposure are listed here.
How far may brilliant indirect light be from a window?
If you are aware of the requirements of your plants and your living space, growing houseplants can be simple. Here are some essential conditions for indoor plant growth.
Light
The amount of household light varies depending on the time of year and the exposure. The most light comes through south-facing windows, which receive direct sunlight up to three feet away, intense indirect light up to five feet away, and semi-shade up to eight feet away. Windows facing east and west let in some direct light up to three feet distant and some indirect light up to five feet away. Sunlight enters east windows in the morning and west windows in the afternoon. Up to five feet away, windows with a north orientation offer some shade.
The season affects the brightness of the light. In the summer, when the light is stronger, plants that thrive in a southern exposure during the winter may need to be moved to an east or north-facing window. Keep in mind that unclean windows can block up to 50% of light; keep all sides of your windows clean. Remember to rotate the pots by 1/4 turn every few weeks to ensure uniform growth since most plants grow toward the sun.
Many plants may survive without natural light sources if they are provided with other forms of illumination. Indirect sunlight or artificial lighting made expressly for plant growth are both sources of light.
Signs that plants are not getting enough light:
- There are fewer leaves than usual.
- Leaf color is faint.
- Plant is growing leggily.
- Lower leaves become yellow and disappear.
- The greening of variegated leaves.
- The plant does not bloom.
Water
The amount of water that a plant requires depends on a variety of factors. In general, larger plants require more water than smaller ones. A plant requires more water when it is blossoming or actively developing (generating new green shoots) than when it is dormant (resting). In comparison to the cool winter, plants typically require more water during the hotter summer months. More water is required by plants in sunny regions than by those in shade. Plastic pots are better at holding moisture than clay pots, which dry out more quickly due to their porous nature. While some plants require regular rainfall, others prefer dry environments. Everything relies on the plant you choose, how and where you grow it.
Correct ways to water your plants:
You can water plants with a watering can, in the sink, or even in the shower. Putting your plants in the shower also offers the added benefit of washing away typical pest issues and wiping dust off the foliage.
Use tepid water and water your plants a lot when you water them. Giving large sums sparingly is far preferable to giving modest sums regularly. The plant should be thoroughly watered by being completely submerged in water, and after letting the top few inches of soil dry out, you should water the plant once more.
Some plants, such begonias, cyclamen, and African violets, don’t enjoy having water on their leaves. Put the pots of your plants in a bucket, bowl, or sink filled with lukewarm water to water them from below. You should either fill the plant’s saucer with water or let the water level drop to just below the pot’s rim. Give it 15 minutes to stand.
Watering Do’s and Don’ts
- Use warm water to make water. Cold showers are unpleasant for both you and your plants.
- To check if the soil is wet or dry, stick your finger or a pencil 1 to 2 inches deep into the ground.
- Instead of often and shallowly watering, do it infrequently and deeply.
- Don’t follow a fixed timetable for watering your plants. First, check them.
- Keep your plants out of water. 15 to 30 minutes after watering, empty saucers of water.
- Avoid watering your plants at night, especially the leaves, since this could increase their susceptibility to disease. Drink water throughout the day, but avoid the midday sun unless they are starting to wilt.
One of the most typical ways to destroy houseplants is to overwater them rather than underwater them. Overwatering causes the roots to decay and stops plants from receiving oxygen.
Temperature
The majority of indoor plants thrive best when kept at 65 to 75°F during the day and 55 to 65°F at night. Many indoor plants demand a 10 degree drop in temperature from day to night. This drop is necessary for some plants to start flowering.
Your home has several different microclimates. In the winter, locations near windows may be sunny, but they are also cool (10colder than the middle of the room). A south-facing window may get too warm for plants in the summer. Open the window to let fresh air in, or buy a sheer curtain to keep the summer sun’s heat and glaring rays out. Look into the microclimates of your house to determine where to place your plants.
Soil
Soil is one of the most vital and sometimes disregarded components for successful indoor plant growth. The potting mix provides stability, water, and nutrients to the plants. Because plants often require efficient air circulation and drainage around their roots, the structure of the potting mix is crucial. Never utilize dirt from a garden that is outside. It frequently weighs too much and can be infested with pests and weeds that could harm your indoor plants.
There are several excellent potting soils available. There are sterilized soil-based potting mixtures and soilless mixtures (which tend to be peat-based). Larger plants that require weight in the containers should use soil-based mixes because they are heavier. Mixtures without soil are lighter.
Potting soils contain a variety of components, including peat moss (which is light and retains water well), sphagnum moss (which also retains water), fir bark (which drains well), charcoal (which deodorizes), perlite or vermiculite (which promotes drainage and aeration), and coarse or sharp sand (drainage). For example, cactus demand a sandy, well-drained mix, azaleas require acidic potting soils, and the majority of orchids require airy, exceptionally well-drained fir bark potting soils.
Humidity and Ventilation
Your home’s humidity throughout the summer is probably between 30 and 50 percent. When the central heating is on, the humidity falls by 10 to 30 percent, making the environment more like a desert. Tropical indoor plants will require assistance in these challenging circumstances. Several methods to support your plant include:
- assemble plants in a group. Plants release water through transpiration, which increases local humidity.
- Put plants on a pebble tray, add water, or let water runoff collect to create a dry well. You have produced a humid local environment as long as the plant’s roots are not in contact with water.
- Consider purchasing an electric humidifier. Both the plants and you will benefit from it.
- Additionally, plants require adequate airflow. Opening the windows on warm days, turning plants that are gathered together so that various sides are exposed to the air, or purchasing a small fan are all ways to increase air circulation. Keep in mind that plants dislike rapid changes in temperature, as well as cold or warm air bursts.
Food
A plant can typically get by on the nutrients in potting soil for two months. You’ll need to fertilize your plant after two months. Water-soluble and time-release fertilizers are the two primary categories. Pick the one that works best for your schedule. Water-soluble fertilizers appeal to folks who love to fuss over their plants, whereas time-release fertilizers are appropriate for busy, forgetful gardeners.
Macronutrients are the three substances that plants require in high concentrations. Nitrogen (N), the primary component of nourishment for foliage plants, encourages the growth of stems and green foliage. Phosphorus (P) is advised to predominate feeds for blooming plants since it promotes root growth and flowering. A greater potassium fertilizer is advised for plants with woody stems and those that bear fruit since potassium (K) contributes to overall stem strength and disease resistance. Ingredients for fertilizer are provided using the N-P-K formula. The formula 5-10-5 stands for 5% nitrogen, 10% phosphorus, and 5% potassium. In modest amounts, plants also require calcium, magnesium, and micronutrients like iron, copper, manganese, and molybdenum.
Some simple rules for fertilizing:
- It is worse to overfertilize than to underfertilize.
- Use 1/4 to 1/2 the recommended strength of fertilizer. Smaller doses are fine for plants.
- Flush your plants with warm water once a month. This will remove hazardous salt deposits from fertilizer that have built up inside the pots.
- After repotting your plants, give them some time to adjust before fertilizing them. The new potting soil may contain fertilizer.
- Fertilize unhealthy plants sparingly. Instead of destroying it with fertilizers that are high in salts and might only make the situation worse, it is preferable to troubleshoot and identify the issue.