Tending for your houseplants can require some time and effort, but all the care put into making sure they look their best is definitely worth it. So, after learning all the necessary steps to take care of their indoor plants, it’s no surprise that some people become frustrated when the leaves on their plants start turning yellow, brown or black.
In order to keep your air-purifying plants looking their best, we need to understand what causes this discoloration in the plants’ leaves.

There are multiple reasons why your houseplants might be looking a little worse for wear, ranging from diseases to simply natural causes. Below, you’ll find some of the common causes for yellowing leaves and how you can prevent it from happening.
CAUSE
|
SOLUTION |
Moisture Stress/Improper watering
Under-watering and over-watering your plant can’t cause damage to the roots and make the leaves turn brown, dry and crispy. |
- regularly check the soil in the plant’s pot
- ensure soil remains evenly moist at all times
- when the top 1 to 1 ½ inches feel dry, it needs to be watered
- trim away the damaged leaves
|
Temperature
Cold drafts on tropical plants will cause leaves to turn yellow. Long periods of exposure to cold temperatures will dry out the leaves and turn them brown. |
- move the plant away from air-conditioning vents
- mist regularly to maintain humidity and prevent drying
|
Nutrient Deficiency
The plant may not be receiving all the nutrients it requires. This could be due to under or over-fertilizing, a nitrogen deficiency, or too much calcium in the water. |
- try your best to diagnose the problem properly before taking action
- learn more about the different cases of discoloration to figure out the root of the problem
- use fertilizer at a labeled rate
|
Lack of Light
Plants may turn yellow if they’re not receiving enough light. Low light limits the rate of photosynthesis. |
- move the plant to a location where it will receive the proper amount of light
- make sure the entire plant is able to receive light, adjust position if necessary
- set up artificial plant lights if window light isn’t available
|
Normal Aging/Disease
These issues aren’t easily taken care of. Normal parts of a plant’s life can’t be prevented. |
- trim back the main stem to promote new growth and bushiness
- discard infected plants to prevent disease from spreading to susceptible plants nearby
- wash and sterilize tools/pots before using on new plants
|
Yellowing leaves aren't the end of the line for houseplants, so it's important to understand what's causing the discoloration so that you can fix the issue before discarding the entire plant. If you follow these steps, your air-purifying plants are sure to look healthy and thriving in any indoor space!
Author: Angela Morilla