It's easy to figure out what type of light your plants need. If they didn't tell you at the plant shop, Google it. But what does "bright indirect light" looklike, exactly?

Categorizing types of light can be particularly difficult indoors, where shade from the trees and buildings outside your window come into play. That's why, in the interest of keeping your and also my plants alive and well, I consulted Joyce Mast, longtime greenhouse grower and the resident "Plant Mom" at online plant shop Bloomscape. (She's also actual mom to Bloomscape's founder, Justin Mast.)

Here's what I learned.

Types of light

First, I wanted to know the basics. How can you tell if light is low, medium, or bright? How can you tell if it's direct or indirect? Do these words even mean anything for real, or were they invented by Big Plant to keep us panic-buying lawn-sized bags of fertilizer?

Turns out, it's a lot simpler than I thought. Joyce explained that light is direct if it shines onto your plant's leaves unblocked and un-diffused. "This usually occurs when plants sit close to windows," she explained via email, although if your window is close to the outer wall of another building (hello, New York City!) the light's probably not so strong.

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Distinguishing low, medium, and bright light can be trickier. Instead of puzzling over whether your window is medium in the morning and low at night or the other way around, Joyce suggested this rule of thumb: "Most houseplants will do best in spots with eastern or western facing windows," she said.

East vs. west vs. north vs. south

East-facing windows, Joyce explained, provide plants with bright indirect light for most of the day, and are ideal environments for money trees, spider plants, and snake plants, among others. Because of the sun's trajectory, west-facing windows generally provide indirect light in the morning and brighter, direct light for several hours during the afternoon.

If the light seems too intense during this time, she said, "move the plant a couple of feet away from the window or hang sheers."

Only have windows with northern or southern exposure? It's not the end of the world, but be careful.

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"Windows with a northern exposure never receive bright, indirect sunlight," Joyce said. "It may be too low for some plants, yet many plants will thrive when placed very close to the window." (She cited bird's nest ferns, calatheas, parlor plants, and ZZ plants as examples.)

"Yes, plants can also be sunburned."

South-facing windows receive the most direct sunlight, and, according to Joyce, are too bright for most indoor plants. (At the very least, Joyce suggested moving them farther away from the window.) However, desert plants like succulents, yucca, and cacti, which are show-offs and accustomed to intense sunlight, will probably love them.

How do I keep my plant happy?

So you've put your plant in the most ideal lighting possible — or at least you think so. How can you be sure you made the right move?

If a plant is getting too much sunlight, you'll probably be able to tell. According to Joyce, scorched plants might have "bleached out" looking leaves, perhaps with light brown edges or spots.

"Yes, plants can also be sunburned," she said.

To revive a sunburned plant, move it to a shadier location immediately. If it lost a lot of leaves, you'll also want to water it a little less until it grows new ones. And don't worry too much. Provided that the damage wasn't too severe, you should be able to get it thriving again.

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If a plant is getting too little sun, it might grow "tall and spindly" as it attempts to stretch toward the light, Joyce explained. New leaves might also rapidly turn yellow. If this happens to one of your plants, don't panic and immediately stick in on a south-facing windowsill, though: You'll risk burning your already-delicate little specimen.

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"Expose the plant to higher light gradually toacclimate a better location," Joyce cautioned.

She also recommended rotating all plants once a week — even if they seem to be doing well — to ensure that they grow evenly.

OK, but what if the light in my apartment sucks?

Unless you literally have zero light in your apartment, you can get something to grow. Joyce recommends the dracaena limelight, a vivid green plant that actually retains its bright hue better in low light environments.

"Their tolerance of a wide range of conditions makes them an excellent choice for the beginner plant owner," Joyce said.

Plus, they're great at cleaning the air.