Plants need light, it’s part of the magic recipe for them to grow healthy and beautiful. But how much light is enough? And more importantly, how do I know I’m giving my houseplant the right amount? Let’s dive in.
Just like humans need food to function, plants use light as a source of energy. Since light is an important part of the growing process, aka photosynthesis, it is crucial that our green friends get the amount they need in order to grow beautiful and lush. If they don’t get the right dose daily, they starve and won’t survive.
Inadequate lighting is one of the most common killers of plants after overwatering. Believe it or not, direct light often burns leaves the same way it burns human skin. And since the majority of houseplants evolved under the partially shady canopies of the rainforest, only some plants can tolerate the intensity of the full sun. Exceptions are plants that live in hot and dry areas, like cacti — they minimize their light intake or protect themselves to prevent burning.
Each plant and its family have different needs. Some plants are happiest in the shade, and those are good for dimly lit corners. Others like direct sunlight, which makes them perfect for windowsills. Finally, some enjoy both light and shade, which makes them excellent fits for a coffee table.
Let’s get into the nitty-gritty: Levels of brightness
Light has 3 levels of brightness (low, medium, and bright), and each plant has an optimal range.
Bright light can be direct or indirect, which is determined by where the sunrays fall. Some plants need direct sunlight, others tolerate it for a short period of time, but most of them need to avoid it.
So, how do I know how bright my space is?
The amount of light your space receives depends on the direction of the window and how far you place your houseplant from it. Use the table below to determine what kind of light your space gets.
[ Graph ]
Keep in mind, however, that the buildings or trees in front of your windows matter. The more obstructed the view, the more it impacts general brightness. We recommend you go one level up in the table if that’s the case. For example, if your window faces East and your plant needs medium light, place it close to it rather than 5 feet away.
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The shadow test in 3 steps
Another simple way to define brightness levels is by the intensity of the shadow. That’s particularly helpful if the view is somewhat obstructed and it’s hard to estimate how much light actually sneaks in. Here’s how to proceed:
- Place a sheet of paper on the spot where you’d like to grow a plant.
- Hold your hand about 1 foot (30cm) above the paper.
- Now, what do you see? Use the graph below to find out.
[ hand graph ]
All plants have a favorite light level range
Plants are very adaptable. Each one has a light level range it feels comfortable in (for example, Snake plants like to be in low to medium light). On the higher end of the range, your plant would get tons of photons and thrive. The lower end would still give it a sufficient amount of light to live happily, but its growth wouldn’t be as fast.
[ graph ]
Now you know how much light your space gets, and you can decide where to put your plant for optimum growth. Make sure you choose a spot that’s going to nourish it for the long term without burning it!
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