How to Use Grow Lights for Indoor Plants (Ultimate Guide)

(Last Updated On: January 15, 2021)

Indoor plants are those greeneries that settle for less light and eventually grow up healthy. As a matter of fact, growing plants indoors with artificial light can make or break your inner horticulturist and your private garden as well.

Simultaneously, you would be amazed, knowing the exact use of grow lights can boost the plant’s manifestation. For the next few minutes, bear with us to acquire detailed knowledge on how to use grow lights for indoor plants.

Types of Grow Lights for Indoor Plants

There is a handful of grow lights in the market that the expertise uses and suggests other newcomers apply in need. Let’s dig a little deeper on those:

Fluorescent Grow Light Bulb

A Compact Fluorescent Bulb/Tube/Lamp produces short-wave light by causing gas redemption from mercury vapor by engaging with electricity. That’s how the phosphor coating inside it glows and forms visible light.

Fluorescent grow lights host almost all kinds of indoor plants. It produces a bright blue color and keeps the surrounding cooler. The beginner gardeners cling to it as it costs lesser and very familiar to use for everyone. Fluorescent lights are a crowning solution for indoor plants that do not have any flowering stage, such as herbs, lettuce, cannabis, and so on.

Metal Halide Grow Light (MH)

Metal Halide Grow Light

Metal Halide, and HID Lights branch, gets power from a mixture of mercury vapor and metal compounds (Iodine and Bromine) while an electric arc runs through it.

MH grow light manages to provide blue wavelengths, which we target to go for a plant’s vegetative stage. It reduces the plant’s chances of stretching out in lack of enough light and resulting in weak branches. To be honest, other than benefitting this particular stage Metal Halide is quite archaic. Yet, a tight budget or combining MH lights with HPS lights can turn the table and make this grow light more effective.

High-Pressure Sodium Grow Light (HPS)

hps grow light

High-pressure Sodium grow light is another HID Lights section that uses sodium, mercury, and xenon gas and heats them to emit light. Whereas each of the gases produces a different spectrum individually; therefore, it ends up in a reddish color.

Considering the visible color, HPS has a stable stand for the plants in the flowering stage. It surprisingly uses less electricity and tends to cover a larger area with taller in height plants. This HPS grow light generates heat in a congested area like a grow tent though applying a clipping fan minimizes it.

Ceramic Metal Halide Grow Light (CMH)

Ceramic Metal Halide is another HID Lights branch that people often confuse with its fellow member Metal Halide. It uses the same gases as HPS, and when a ceramic arc runs through the vaporized mixture, it produces more efficient light than other HID programs.

In simple words, CMH has outweighed all the shortcomings that other HID bulbs were holding. CMH applies less energy to glow up; still, it provides a higher PAR rate, which immensely changes a plant’s life.

It produces less heat than other HID lights, and in the case of durability, CMH is on the winning side again. Because of its red-yellow outcome, HPS light or another solution for the thriving stage will always be an urgent need.

LED Grow Light

LED Grow Light

The light-emitting diode has a built-in semiconductor (P-type and N-type) where direct electricity flows to generate a massive amount of light.

LED grow lights for indoor plants are so far the best-advanced option to grow houseplants gracefully. Comparing other grow lights, LED’s are expensive than any typical range of budget.

It minimizes electricity bills even after using extended time, lasts longer, covers larger grow space, does not produce heat, and the list goes on. In contrast, it totally does justice with the cost it has taken.

How Far Should You Place A Grow Light?

Suppose you have finally picked the growing light, and the next debate will always be fixing an ideal distance between the lights and plants. In truth, there are 2 conventional ways all gardeners tend to follow.

Either you set up the light just as another traditional light at home, or you check the light’s power, reassure the plant’s life stage, and measure the accurate distance like a wise plant raiser. Not to mention, with the increasing height of growing plants, the safe space needs to recheck and maintain accuracy.

Whether natural or artificial, any light source does not focus only on the plants; instead, it spreads all over the place and wastes a lot of it. Measuring the wrong distance might cause more waste or burn out the leaves.

The weaker or stronger a grow light is, the closer or farther it should be positioned. And so, here we go, to have a clear conception of where should you place a grow light based on the power and plant’s growing stage:

Fluorescent Grow light Bulb

The more lumens at work per wattage, the more efficient a grow light can be for a plant. It produces 30-110 lumens per wattage and considered low powered grow light compared to others on the count.

According to that, achieving more lumens for each leave the fluorescent light needs to be at a distance of 6-12 inches from the plants. As this grow light is a chilled one, so the risk of burning leaves is out of the list even on this close range.

However, the distance needs to readjust and decrease the length, especially at the thriving stage.

Metal Halide Grow Light (MH)

Metal Halide has 75 to 100 lumens in each wattage. It covers 2×2 square feet with a 150-watt bulb finely. With the increase of wattage in an MH light, it increases the number of lumens, and that’s where more and more heat generates.

Because of that, the light must keep a distance of 8 inches from a plant at any stage. For better understanding, a 150 watt MH light has to fix at least 8 inches away, and with the increase of every 100 wattages, the distance needs to add 2 more inches as well.

As the counting goes on, an MH light with higher wattage (1000w and more) can be 31 inches furthest to work and keep the temperature balanced.

High-Pressure Sodium (HPS)

Among all the grow lights around, HPS Lights offer the highest range of 60 to 140 lumens per wattage. Even so, the heat generated by it you cannot overlook.

And so, a 400watt HPS light requires a distance of 12-19 inches. As the wattage rises, the light can stay at the highest reach of 31 inches at most for 1000 wattage. Formed on that, the watts of HPS in between (400-1000) fall in a safe distance around 15-30 inches, which can be experimented by you where it works more significantly.

A plant in the flowering stage would demand more lumens from the HPS grow light. Not ignoring the fact, the heat will harm the plants if we bring the lights any closer than we have already calculated. To improve, combining these HPS with a few fluorescent lights and decreasing the distance might help in this delicate stage.

Ceramic Metal Halide (CMH)

Ceramic Metal Halide produces around 95 lumens per wattage. Simultaneously, it has extensive amounts of heat, which knock off its advantages to some extent, unfortunately.

A CMH light appears with 400watt/600watt or 1000watt typically. Observing the heat in the environment and the wattage, the light needs to hang at a distance of 18 inches to 3 feet top from the plant’s surface.

While plants will ask for more light at the fruiting or flowering stage, you can lower the CMH light a little bit before that, attach a fan nearby to clear away the heat, and monitor the temperature from getting overheated.

LED Grow Light

LED Lights manage to generate 60 lumens per wattage, rises to 300 lumens per watt depending on the total wattage a single package is holding. It doesn’t make any change visible in the weather around and is mostly known for serving heatless light.

Though it doesn’t burn out the leaves, the excessive power can harm differently in the thriving stage of a plant. That is why

  • 250-400wattage LED has to maintain a distance of 12-25 inches
  • 400-600wattage LED has to keep a length between 20-30 inches
  • And from600 to 1000 wattage, any LED light has to maintain a distance of more or less 36 inches.

The plants in the flowering stage need more light. Only around this time, LED light is allowed to stay a little closer than before, making the lumens more available to needy plants.

Benefits of Different Colors in Indoor Plants

Most of the grow lights are full-spectrum, and it is wide-spread that plants have an inevitable requirement of red and blue light in a ratio of nearly 5:1. In this manner, these two colors play the lead role in the story, while the rest of the colors have to accomplish an episodic need.

Therefore, applying the right color at the right time doubles the growth rate of any plant. Now let’s get a detailed overview of these colors and their participation in a plant’s life.


The blue wavelength is the essential light for a plant’s initial life. It directly gives a head up to chlorophyll to photosynthesis and converts the light energy into its strength.

Precisely, the reason why grow light with a blue spectrum is the best grow lights for seedlings. So, it can win over the thriving stage easily and continue to be a vigorous plant.


After passing the yielding, the plants ask for more energy from lights, mostly from red grow lights. A red light source makes the plant go on without sunlight in the vegetative, flowering, and fruiting stage.

A plant in a developing stage requires red light to improve its blooming and stiff structuring. Without it, growing an indoor plant any further is absolutely impossible.


Don’t confuse yourself by thinking the yellow marks in a leave comes from the yellow light. In reality, indoor plants have nothing much to do with the yellow spectrum. Still, using a yellow wavelength once a while will make sure to reduce the risk, if the plant has any.


Scientifically, the green light reaches deeper to the photoreceptors where no other color could come and fulfills the plant’s need. It is inappropriate to say that the green leaves get the whole spectrum from it, but the plants need green lights to make some work done for sure from time to time.

How to Install LED Grow lights for Indoor Plant?

As you read each word of this section, after assembling an insight of grow lights, now is the moment of practically installing and experimenting with one. Being said that, Bestva introduces us with one of the Best Led Grow Lights For Indoor Plants.

As the planters have an immense curiosity towards LED lights, let’s get on work to set a LED light for indoor plants.

Step-1. Determine the Plants You Will Be Growing

For the plants, you plan to grow under LED light, note down their basic needs to grow healthy. Any plant on average needs 300-800 lumens, but the numbers can change depending on the plant. That is why google it or better know it from an expert how much light energy it requires to grow cheerfully.

Step-2. Have A Clear Idea About the Grow Space

Any congested area would need lesser light, and the bigger space, the more light the plant would demand, no doubt. To avoid the plant’s stretching out, map the area of planting, and measure the number of lights you would need to cover the whole mapped area.

Step-3. Pick the Best Suited Power and Color of a LED

By this time, we assume, you have selected the plants and space of your planting. Based on that, pick the suitable wattage that can easily roll the light over on the whole place to provide equal lightening on each plant and complementary colors for those plant’s growth.

Step-4. Calculate the Distance between the Plants and LED Light

Now that you know your LED light’s power rangeso go back a few lines where how the distance should be depending on the wattage has explained. Or follow this quick remark; for the least wattage to highest, you can use the distance from 12 inches to 36 inches at most.

Step-5. Fix the Light in the Decided Position

To fix the light in a grow room, you might have to arrange a sturdy holder to hang the LED light, whereas everything is already sorted out in a grow tent. All you would need to do is measure the distance and confirm a firm hold.

Step-6. Rotate Your Plants

After following all the previous steps, rotating your plants around the room is reassuring to overcome deficiency if the whole process had any.

Step-7. Keep Track of Growth and Be Specific with the Duration of Active Lighting

The distance, color, or power anything might need to readjust. Always keep a record of the plant’s growth topredict if something is going wrong with it instantly.

Another important fact, the duration of using the light must pursue strictly. With the timer, controlling the schedule of turning the light on and off has been a lot easier.

The Closure

Grow lights are a necessary substitute for sunlight for an indoor plant. We have tried to explain and provide answers to your confusion thoroughly on how to use grow lights for indoor plants. The proper understanding will bring a massive change and make you a pro-horticulturist in the fastest time.

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