How to measure light for plants is important when you can easily see the brightness of the light with your eyes. As you master the level of measuring, you will be able to evaluate the light levels your plant received based on the light source if the brightness is deceiving.Measure Light For Plants in Various Ways

For instance, if there are some barriers that hinder that light from reaching your indoor plant, then your assumptions would be completely wrong.

This article has given you the basics on how to measure light intensity on various plants, how to measure light for indoor plants, and the steps for using the best light meter for plants so read on.

How to Measure Light For Plants in Various Ways?

To measure light for plants in various ways, you can opt to use the shadow method or try functioning with the application. You can also use a light meter or even rely on the direction you face when placing your plant near the window.

Light is part of plant care, and it is never complete when you cannot implement proper measures for assessing the amount of light that your beauties receive. It’s also vital to know the type of exposure that your plants require, be it direct sun or bright, indirect light.

Most indoor plants are sensitive to direct light, and it is important that you would consider the type of plant you have.

– The Shadow Method

This method is effective when you implement it during the time when the light intensity is at its highest levels. All you need is your plant and hand; then you can measure light exposure for your plant because a common house plant must receive between 7,000 and 7,500 lumens, ideal for growth and survival, which should be considered.The Shadow Method for Highest Levels Light Intensity

The first step to measuring light is to place your plant at a spot that will give it the amount of light that it requires. Then, during the noon time when the light is brightest, hold your hand up and analyze the appearance of the shadow, this is the key option you need when you are targeting the manner.

On the other hand, if the light intensity is high, the shadow of your hand will be crisp and well-defined. Low amounts of light are characterized by faint shadows, with an unclear outline, which would be a way to notice it.

Moreover, you must also consider one of the advantages of this method is that it is cost-effective, considering that you don’t need any expensive gadgets to use. However, it is one of the least effective strategies for measuring light as the results are relatively imprecise. You can use this method to give you a general idea of the amounts of light your plant is exposed to.

– Functioning With The Application

If you have a smartphone, you can measure light in the form of foot-candles using a light meter. Use this function, which is a fair amount considering the importance of understanding light exposure parameters for your plants, to be very precise about the plants that you are growing the plant.Functioning Light With Application

You can download the application and choose the “outdoor setting,” regardless of whether your plants are indoors because this is where you will be placing the plant. Now, to measure the light, ensure that your camera is pointing in the direction of the light and that you have the leverage to use either the back or front of your camera.

Before you would go ahead and read the measurement, you must tap on the “sun button” if you want to measure the illumination once, or you could tap and hold if you prefer the real-time measurement mode. This is how it will be very strict on the right way of measuring this indicator.

There are many other light meter apps that exist, and these would all aim for the same result, overall. Although some of them measure light in foot candles, most of these light meter app tools give results in LUX. Using this formula, you can easily translate LUX to foot candles: 1 lux = 0.0929 foot-candle.

When you have this application, you must just hold the meter such that it faces the light source. Notice how the meter does not need to touch any part of the plant, though it should be in proximity. Get the reading on the meter and interpret it using the hand chart that is often found together in the process.

– Use a Light Meter

Using the light meter, you can always go right in measuring light. If you are looking for the best light meter for indoor plants, there are different options that you could consider. Begin by taking off the cap from the sensor of the meter. You can then switch the device on, before pressing the labeled FC or LUX button once.Use a Light Meter fpr Plants

Now, you must note that switching from LUX to FC on the bottom right side of the screen is possible. Press the “range button” as many times as possible, until a reading is displayed. Doing this will assist you in finding the range that better matches the space that you are testing. Go ahead now and hold the meter as close to your plant’s leaves as possible, ensuring that it faces the light source.

This method of measuring the light using light meters is the amount of light that comes from the source of light, even grow lights. It doesn’t take the light that bounces off the leaves into consideration.

Suppose your plant is positioned in such a way that it is close to a wall; you can assess the light amounts that reach the back of the plant by holding the meter close to the wall. In this case, the differences in the levels of light received by the plant’s front and back sides will confirm why it is important to regularly rotate your plants so that they all get adequate access to sunlight or grow lights.

– The Direction Faced by Your Window

You can determine how much sun your plant gets based on the assumptions on the amounts that might be getting through the windows. For example, in the Northern Hemisphere, the sun rises in the east and sets in the west.Light Direction Faced by Window

In this case, the amount of light that your plant accesses through the window differs as the sun moves from the east to the west. Not only that, the levels of the light that gets through your window also vary based on the year’s season and where you are placing the plant.

In the Northern Hemisphere, windows that face the north bring in the weakest light, so this is because the path of the sun is on the southern side of the sky. To get the best of the light in such scenarios, you can place your plant as close to the window as possible and still not worry about them getting burned. This is not the same as west-facing windows that expose your plants to intense light that can fry the leaves of your plant.

The light that comes through the east-facing windows is the best when you are growing houseplants. Your plants will get the direct but gentle morning light, so it would be great for plants that belong to the Calathea or Malanta families.

If you are growing plants that prefer consistent exposure to light in the Northern Hemisphere, it is ideal that you go for placing them close to the south-facing window. Again, this is because the plant is predominantly on the southern side of the sky.


Evaluating the amount of light your plants are getting has never been that easy, especially with the information provided in this article. Here are some highlights of the main points once more:

  • For more accurate results in measuring the intensity of the light that is available to your plants, use the light meter, and it will determine.
  • The shadow method is one of the less expensive strategies that you can employ, though it’s not as effective as the light meter.
  • You can also download the application from your smartphone that will help you to measure the light that comes into the room.
  • The direction of the window where your plant is positioned can also give you a general idea of how much light it is exposed to.

Now that you know the right way of measuring the light in the right way, you can go ahead and try it and give your plant the best location and light they will thrive in.

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