How to Measure Light for Houseplants

How to Measure Light for Houseplants

Let me start by saying that it is challenging to asses proper lighting for our plants! Different people perceive ‘bright indirect’ in so many ways. What you think as ‘bright’ might not be the same brightness we have in mind when it comes to where the plant should be placed. Will the plant be happy at the spot you have chosen?

One of our job requirement is to make sure the right space for the right plant. Trust me, it goes a long way!

Nature, meet Technology

Good things can come in free packages. We have identified two free apps on both iOS and Android that could help all of us in finding the sweet spot.

Difference between Foot-Candles and Lumens

First, we need to know the difference between these two reading output that is currently used in measuring light and supported in free mobile apps.


A unit of measure for quantifying the intensity of light falling on an object.


A unit of measure for quantifying the amount of light energy emitted by a light source.

In short, lumens is a better reading if you were to test a light bulb of 60W and 100W. In our case, we suggest to use foot-candle, which is common in horticulture.

Which App to Download?


Light Meter by Elena Polyanskaya


Lux Light Meter by Doggo Apps

How to Use?

For iOS, refer to the below instruction;

Click FC in the middle, select Outdoor even if you’re indoor, lastly click on the Sun button in the middle to get the reading.

For Android, ensure that your screen is facing the light, as the sensor is on the front screen of your mobile. The reading is automatically displayed as you switched the app on.

What Does it Mean?

Determine the amount of sunlight needed by identifying your plants below

Low (50-250FC)

Placement: few feet away from the window

Medium (250-1000FC)

Placement: next to a window

High (1000-2000FC)

Placement: balcony or under direct sunlight

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  • The Plant Newbie: Plant 101 – Reply

    […] Plants appreciate adequate natural sunlight. The sun acts as a form of energy to plants. Their leaves absorb sunlight and convert it to energy for growth. Lucky for us, Malaysia is blessed with ample of sunlight all year round! Naturally, plant placement in your home or office plays an important role to ensure that they are happy. Choose a spot where your plant will get lots of bright indirect natural sunlight. Examples of plant placement in your home or office would be by a bright window with curtains / blinds open majority of the day. Or by a balcony sliding door. A south, east, west facing window or balcony has the best sunlight. A north facing window provides the least amount of sunlight.To measure light in your office or home, download a Light Meter App to measure sunlight in your chosen spot. The Light Meter App is available for download on Android and Iphone. Read more about this here […]

    October 7, 2018 at 5:45 am

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