The Garden Decoder: What Do ‘Low Light’ Conditions Really Mean for Houseplants?

I understand the difference between shade, part-sun, and full-sun plants when it comes to outdoor plants. (Need a refresher? See Houseplants: How to Decode the Info on Plant ID Tags.) But when it comes to indoor plants, I’m completely flummoxed by their light requirements—especially when the plant tag says “low light.” Houseplants are by definition indoors, and aren’t indoor conditions always low-light when compared to outdoor light?

Let’s investigate.

Featured photograph by Mimi Giboin, from Best Houseplants: 9 Indoor Plants for Low Light.

What do “low light” conditions really mean?

The intensity of sunlight is always going to be brighter outdoors than in; the shadiest spot in your garden still gets more light than the brightest part of your home. But the quality of the light streaming into your home is different depending on its distance from the light source (usually a window). “Bright light”conditions when talking about houseplants means there’s nothing blocking the sun from reaching your potted plant—no curtains, no shades, no trees, no tall buildings. “Medium light” is when there’s, say, a sheer curtain between the light source and your plant. “Low light” is when your plant gets no direct light, likely because it’s placed several feet away from the light source. For a list of plants that thrive in low-light conditions, see Best Houseplants: 9 Indoor Plants for Low Light.

What part of your home is best for low-light plants?

Consider rooms with north-facing windows (south- and west-facing windows get the most light) or rooms that are dark because of tall buildings or trees that block the sunlight. A spot that’s away from windows, like a dining table in the middle of a room, can also be ideal, no matter which direction the windows face.

Can a low-light plant survive in a windowless room?

Low light doesn’t mean no light. But that doesn’t mean a room has to have a window in order for a low-light plant to survive. As long as you give the plant some ambient artificial light—via incandescent bulbs, fluorescent lights, or LED lights—it should be fine (and maybe even thrive). This is good news for cubicle dwellers who want a little greenery on their desks.

For more on houseplants, be sure to read 10 Things Nobody Tells You About Houseplants. For more in the Garden Decoder series, see:

• The Garden Decoder: What Is ‘Square Foot Gardening’?
• The Garden Decoder: What Is ‘Lasagna Gardening’?
• The Garden Decoder: What Are ‘Biennials’?