Is A Grow Light Considered Indirect Sunlight?

Few things cause more consternation among gardeners than the idea of brilliant indirect light.

While a basic definition of strong indirect light may be simple regarding its actual application, you must consider several factors.

People interested in indoor gardening are usually concerned about the differences between strong indirect and direct light for plants.

In this article, you’ll learn how much and answer the common question, “is a grow light considered indirect sunlight?”

Grow Light

Grow Light
Grow Light

Firstly, let’s find out some fundamental information about growth light (artificial light).

What Is Grow Light?

Artificial lights, called “grow lights,” encourage year-round indoor plants.

To meet the demands of a wide range of plant species, grow lights may be purchased in various color spectrums and ambient light configurations.

When natural light is unavailable, interior grow lights are an essential gardening item that may provide enough lighting for indoor plants.

Functions of Grow Light?

The light source is the photons, which are powered by electrical energy and promote photosynthesis and, in turn, plant development.

The finest light beams for photosynthesis have a wide selection of wavelengths, or colors, to the visual system.

For example, fruiting and blooming plants benefit most from red light, whereas green plants get the most improvement from blue light.

Types of Grow Light?

Your indoor garden might benefit from one of many different kinds of grow lights.

  1. First, there are fluorescent grow lights, which may be tube or compact fluorescents (CFL).While fluorescent lights provide a broad spectrum of light, beneficial for plants, they are far less powerful than light bulbs and can generate hazardous heat levels.
  2. Some farmers still choose incandescent bulbs, even though their high heat production is detrimental to plant growth. Compared to other grow lights, incandescent bulbs are more affordable. However, they consume more energy as well as burn out more quickly.
  3. LED (light-emitting diodes) grow lights last far longer than traditional incandescent or metal-halide light bulbs. They generate little to no heat and use very little energy. There are two common forms of LED lighting: compact fluorescent bulbs and permanent ceiling or wall mounts.
  4. High-intensity discharge (HID) grow lights are the most accurate representation of natural light and are used in commercial greenhouses. These pricey, high-output lights are often only seen in professional grow facilities. Elevated sodium (HPS) lights generate a red tint, whereas ceramic metal halide (CMH) lamps produce a blue color, making them ideal for seed beginnings.

How To Use Grow Light

Grow lights accelerate and improve indoor plant growth.

  1. Select gear: Choose the correct light for your plants and herb garden. Ballasts control fluorescent as well as HID growth light intensities. Indoor plants benefit from full-spectrum grow lights. If you have numerous seedlings, use a bigger grow lamp, panels of lights, or a diffuser to provide more light to the leaves.
  2. Light up: Indoor garden lighting depends on the plant’s kind. Most plants—especially succulents and blooming plants—need intense light.
  3. Check light temperature: Grow lights may burn houseplants, depending on wattage. Keep incandescent lights two feet from plants. Restrict fluorescent and HID grow lights 12 inches from plants. LED grow lights may be six inches from houseplants because of their minimal heat output.
  4. Timer: Plants are harmed by constant light output. Use a timer to control your grow lights’ light for houseplants. Ensure your plants receive a minimum of eight hours of darkness and eight to sixteen hours of light.

Is A Grow Light Considered Indirect Sunlight?

Is A Grow Light Considered Indirect Sunlight
A Grow Light Considered Indirect Sunlight

The “strong, indirect light” that your plants need has been thrown about a lot. The sun provides this kind of indirect illumination. It will initially deflect off of an object.

When illuminated by indirect light, plants grow in murky shadows (800 to 2,000-foot candles).

So, are grow lights considered indirect sunlight?

One way to think of a grow light is as an alternative to or in addition to direct sunlight. Therefore, gardeners took the intensity of grow lights into consideration.

Lights used for cultivating plants are often dim and indirect.

Lighting from the sun may be either direct or indirect. Where and how much sun a plant receives are key factors.

Light from certain sources may be very bright, comparable to the sun’s. The indirectness of the grow light, like that of natural sunlight, is a function of its placement and intensity.

Your plants will only be burnt if you properly set the grow light’s intensity, wattage, and distance.

Comparison: Direct Sunlight vs Grow Lights



As a general rule, plants do better when exposed to sunshine. However, red and blue light is the most beneficial to plants from the sun (direct light).

Therefore, the University of Minnesota Extension experts suggest using red light for flowering and blue light for leaf growth.

While regular fluorescent bulbs mostly create blue light and incandescent light only releases red light, full-spectrum grow lights are created to provide this whole spectrum.

Full-spectrum growth lights are equivalent to natural sunlight.

Low-light plants tend to die. Plants may turn pale yellow or white. There is a chance that the plant may not bloom and may even lose its leaves.


It means strength of light. Houseplants that need a lot of light to thrive inside benefit greatly from growth lights.

When sunlight (direct light) enters a room via a window that filters light for plants or morning light, it is softer and less direct than when it enters directly (less light intensity).

Grow light intensity should be hung at most 6 inches from the tops of plants, as advised by the University of Vermont Extension.

A reflector for grow lights focuses and amplifies the illumination. Plants that like the shadow may thrive in rooms with only indirect sunlight.

Light Requirements

Plants that require a lot of sunlight thrive best when grown under artificial grow lights instead of windows. The saplings and sun-loving plants benefit greatly from full-spectrum bulbs.

Indoor artificial lighting outperforms sunlight reflected via a window but falls short of direct sunlight. The same amount of growth may be achieved in only 6 hours of direct sunlight with 12 to 14 hours of growth light.

Plants that can thrive in dappled sunlight or partial shade require six hours daily under artificial lighting.

Temperature Regulation

An increase in indoor temperature is possible when sunlight enters a room via a window, a phenomenon known as the greenhouse effect.

This is useful whether working with heat-loving plants or in a chilly greenhouse. However, this may be detrimental to plants that thrive at lower temperatures.

A constant temperature of about 70 degrees Fahrenheit is ideal for growing most plants, which is often easier to achieve when using grow lights.

The cold is a further potential hazard. While the brilliant sunshine of winter is great for plants, leaves that come into contact with the cold glass or become near drafts might be damaged.

Again, growing plants using a grow lamp is the best solution if they have specific temperature needs.

Which Light Promotes Plant Growth More Effectively?

Which Light Promotes Plant Growth More Effectively

Every plant has its unique light requirements. For example, some plant species that thrive outdoors fare best in full sun, while others do well in partial sun or complete shade.

Usually, houseplants thrive when exposed to indirect, bright light. Before purchasing plant lights, make sure you know your particular plant’s needs.

Your plant may need more if it struggles to grow, becomes lanky, or produces a few little leaves.

First, before the plant’s general health quickly falls, it is crucial to rectify the lighting condition. Then, get the lowdown on what your houseplants need to thrive by reading on.

Ways To Measure Indirect Light

Using Light Meter
Using Light Meter

Gardeners may measure indirectly-emitted sunlight in two ways. First, gardeners may take measurements of indirect, luminous light with the following:

Using Light Meter

Natural light is the gold standard for light meters. Priced between $20 and $30, light meters are a reasonable investment.

Just prop them up over a plant and point them toward a window or other source of natural light. The meter will tell you how much light your plant is getting.

Most plant life thrives best in conditions of intense indirect light (at least 3,000 lux). Ten thousand to fifteen thousand lux will promote rapid and contented plant growth.

Home illumination changes throughout the day. Throughout the day, readings from light meters will shift.

Using Light Meter App

Many individuals often choose light meters over applications. The explanation is straightforward, so let me explain.

As they aren’t fine-tuned for various mobile phone models, these applications need to be more accurate. Therefore, they need a light meter for calibration. As a result, such programs have no use (and are futile).

One app, called Photon, comes highly recommended by me. The fact that it has been optimized for use on various mobile devices sets it apart from similar programs.

Nine times out of ten, it displays the proper measurements, at least in my experience.


Is Light Passing A Window Direct Sunlight?

YES. Window light is direct sunlight. Direct sunlight—even via a window—hits your plant’s leaves. Direct sunlight via a window is weaker than outside sunlight.

However, it’s still direct sunlight because sunburns may occur via windows that filter light for plants. If your plant faces a white curtain, it receives indirect, filtered light for plants.

How To Give Bright Indirect Light With Grow Lights for Your Plants?

Your plants will do best in the area farthest from the main light source or on the window ledge, where they will get indirect light. Make sure it’s right next to the glass. Position yourself, preferably next to a window.

How to create bright indirect light with grow lights? If your home has a lot of windows, the northern or southern one is the best bet.

The windows on your plant should face north (North-Facing Window) and not be blocked by trees or buildings.

What Happens If A Plant Is Exposed To Too Much Indirect Light?

On the contrary, a plant cannot get too much indirect light. Therefore, for optimal plant health, indirect light is preferable.

A plant that receives sufficient light and lives in proper light conditions will grow larger and more quickly and be in better health overall.

In addition, it is also based on what type of plant you want to grow.


“Is a grow light considered indirect sunlight?” The answer is that the grow light can be considered an alternative or addition to direct sunlight.

But, first, it was thought about how bright the grow lights were. Determining the distinction between direct and indirect light for plants can be confusing.

When a healthy plant needs indirect light, gardeners can choose sunlight (shaded light) or grow lights, as long as you place the plant in the right place and ensure they have sufficient light.

When you use a grow light, you can change its intensity and temperature to meet your plant’s needs.


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Hello I am Samuel. Samuel's Garden is a garden blog where I share my experiences in garden caring and tree growth. Hope you enjoy it!

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