Understanding lighting for growing plants indoors

Low light, indirect light, high light, bright light, direct sun-what does it all actually mean? When it comes to growing indoor plants, one of the hardest concepts to understand is lighting. Setting up your plants with correct lighting will aid new plants with acclimating to new growing conditions and is crucial for new plant growth and also, for the longevity of a plants' life.

Researching your plant and its lighting needs

The first step in setting your plant up for success, is doing a little bit of research on your plant. This research will help you understand the type of lighting it receives in it's natural environment. Do you have a cactus that needs a lot of hours of bright, direct sunlight? Or do you have an understory plant that grows amongst the shaded trees in the rainforest? Seeing how your plant grows in nature will give you an idea of what kind of lighting to give your plant at home and set it up for success right from the start.

Breaking down lighting jargon

If you've done any sort of research on any plant, or even being in the plant community, you see so many references to different types of lighting. Here are some of the most common words you might come across and what they mean.

Indirect light:

I like to think of indirect light as shaded lighting. Or, the difference in standing right under the sun on a hot day versus standing under a tree. If you have a bright window where a lot of intense light pours in, adding a sheer curtain to your window treatment will help give your plant indirect light. If a curtain isn't an option, move your plant off to the side or a few feet away from the window.

Direct light:

Direct light is when you have sunlight pouring directly into a room. This is usually in those sunny, hot room with South or West facing windows. Direct sunlight is when sunlight is directly hitting the foliage of a plant.

Low light:

Low light refers to any place that receives a minimal amount of sun light, or is an extremely shaded area. Low light does not equal no light.

Natural light:

Natural light is any light coming directly from the sun and not from fluorescent lights or grow lights.

Supplemental lighting:

Supplemental lighting is when you need to add in extra lights to aid in plant growth. People like to add in supplemental light when fall and winter come around and the amount of sunlight hours your plants receive is cut back.

Foot candles:

Foot candles is a type of metric used to measure light intensity. This is best measured using a light meter.

Too much light vs too little light

Another good way to fully understand lighting and how much to give to your plants, is understanding what your plant is telling you. Plants will always show signs if they're receiving too much light or too little light.

Signs of too much light

When a plant is receiving too much light, many times, you'll notice scorched foliage. The foliage will look brown or black and burnt, especially the tropical plants with lots of foliage. Another common sign, is bleached leaves. Bleached leaves may look pale or even slightly yellowed. These leaves don't always fall off the plant, but they'll gradually change colors.

If your indoor plants are showing sings of sun stress, move them a few feet back. If they're under grow lights, move the grow lights higher or moving the plant off to the side.

Signs of too little light

The biggest sign you'll notice in your indoor plants if they're not receiving enough light is stunted growth or overall, lack of growth. Another big sign of lack of light is 'leggyness'. A leggy plant is when a plant drops all its lower leaves due to lack of light. The plant will hold onto the new leaves and drop lower leaves to help preserve energy.

If your indoor plants are showing signs of too little light, you can cut and propagate the leggy parts. Click here if you want tips on propagating plants. Next, add your plant to some adequate light. This can be done by adding a grow light or bringing the plant closer to a light source like a sunny window. Never directly put a plant in full sunlight, if it's not used to it. This will cause stress and leaf burn. Instead, gradually introduce your plant to it's new lighting conditions.

Low-light houseplants

If you want the feel of an indoor jungle but like adequate light, these low light plants might be perfect for your place. And remember, low light does not mean no light. All plants require some sort of light in order to correctly photosynthesize and grow.

Snake plant

Snake plants are a great beginner plant and low maintenance. In low light conditions, they require minimal waterings and can be a 'set and forget' type of plant.

Snake plant on a plant stand next to a window
Photo by Kelly Sikkema on Unsplash

Pothos

Pothos add the perfect type of jungle vibes to any indoor area. The long, vines can be added up a wall to create a living wall. While they won't grow as fast in low light, they'll still put out new growth and be a true beauty.

Maranta/Prayer plant

Prayer plants are great low light plants. They keep that gorgeous lime green color and will eventually trail beautifully down a shelf or planter. Make sure to keep up with watering, don't let them dry out, and keep them in a fairly humid environment.

A trailing maranta in a white planter
Photo by feey on Unsplash

Medium-light houseplants

Medium light plants are great for a room with lots of shaded windows. If you ever feel like your medium light plants aren't receiving enough light with the shaded windows, simply add a grow light for supplemental lighting. Click here if you want to know more about grow lights.

Monstera Deliciosa

Monstera Deliciosa is a great medium light houseplant. They don't like super bright light, these are understory plants and the foliage can easily burn when expose to too much light, too fast.

Peace Lily

Peace lily are always a fun genus of plant to grow. They are the divas of the plant world, because they can easily wilt if you miss one watering. But when met with the right conditions, they will thrive in any sort of medium light conditions.

Mini Monstera/ Rhaphidophora Tetrasperma

Mini Monstera is one of my favorite medium light plants. They're don't require too much particular care but will continue to reward you. They look stunning growing up any wall.

High-light houseplants

High light houseplants usually require a few hours of direct sunlight. This is great for any room with a lot of bright, natural sunlight or even if you want to puts some indoor plants outside for the growing season.

Cacti

Cacti are a great option for a high light plant. It's incredible to see how fast a cactus will grow when given the right type of light. There's an array of cacti to pick from as well.

A cactus in a terra cotta pot
Photo by Annie Spratt on Unsplash

Hoya

Hoya are a fun genus to grow in high light. Many different Hoya species will get beautifully sun stressed leaves when given a lot of light. This sun stressing can be orange or red. And, depending on the species of Hoya you're growing, the extra light and even help your Hoya flower.

String of Pearls

I never like to recommend String of Pearls, because they can be quite finicky and die easily. However, if you have the right light and can figure out a good watering schedule, String of Pearls will thrive and can be a true beauty cascading over and plant shelf.

Try adding a trellis to some of these plants. Trust us, your plants are going to thank you if you give them the right support!

Check out our various plant supports.