Any house plant owner can relate to the doom and gloom you feel when you discover a yellowing plant leaf. It can seem like the end of the world, even to us veteran plant owners because like it or not, yellowing leaves on plants can be caused by a variety of different things! If you’ve noticed yellowing leaves on your pothos, fiddle leaf figs, snake plants, ZZ plants, or even Calatheas, here are five reasons why that might be occurring in your indoor garden.
Reason #1 For Yellowing Leaves On Plants: Incorrect Watering
If you’re noticing yellow leaves, the first thing you should do is check the moisture levels of your plant’s soil. If the soil is still decently moist and it’s been more than a week since you’ve last watered, your plant could be suffering from root rot. You’ll want to repot it into fresh soil ASAP as root rot is deadly once it gets going. Use this guide of mine to figure out how to treat root rot in house plants and get your plant looking like new again.
If your plant leaves are yellowing but it’s been a while since you’ve watered, take a closer look at the plant. Are the old leaves or new leaves yellowing? Are the green leaves droopy? If the yellowing is affecting the oldest leaves first and the green leaves look droopy and wilted, your plant likely needs a good watering. Give it a good soak ASAP!
Reason #2 For Yellowing Leaves On Plants: Nutrient Deficiency
House plant leaves commonly turn yellow when the plant is suffering from some kind of nutrient deficiency like potassium or nitrogen. Both will cause yellowing leaves and stunted growth in house plants, so it’s best to supplement with a homemade liquid fertilizer the next time you do your watering. Find my three-ingredient house plant fertilizer recipe here.
However, too MUCH fertilizer can also cause yellowing plant leaves. Keep in mind that almost all house plants only need to be fertilized twice yearly (once in the Spring, once in the Fall) and anything more will likely cause a fertilizer buildup.
If you’ve recently fertilized and are still struggling with yellow leaves, it’s likely another problem.
Reason #3 For Yellowing Leaves on Plants: Too Much Salt
If you suspect excess fertilizer is the reason for your yellowing leaves on house plants, you’ll need to flush the excess minerals from the soil ASAP. To flush the soil, pour twice as much water as would normally fit into your pot into the pot and let the water run completely out. It’s best to do this in someplace like a bathroom. The water will carry away any excess minerals.
(Psst…you can also get too many minerals from tap water if you live in a city that mineralizes the water!)
Reason #4 For Yellowing Leaves on Plants: House Plant Pests
No one wants to hear that yellowing leaves can be a result of house plant pets, but unfortunately, it’s true! Yellowing plant leaves are a common symptom of gnats and spider mites.
Learn how to diagnose your plants with scale here, spider mites here, and fungus gnats here. Not only will I walk you through what each infestation looks like, but I have a few great tips for treating the pests ASAP as well!
Reason #5 For Yellowing Leaves on Plants: The Wrong Amount of Light
House plants are pretty finicky and too much (or too little) sunlight can also cause yellowing plant leaves. Plants like pothos, Calatheas, and ZZs do well in bright, indirect light and too much sunlight can cause their leaves to crispen and burn. If you suspect too much light is common for your yellowing leaves, the edges will be dry and crispy.
On the other hand, too LITTLE light can cause Fiddle Leaf Figs to turn yellow as well. For light-loving plants like cacti, Fiddle Leaf Figs, and other succulents, place them in areas that get at least 6 hours of direct sunlight every day. Your plant leaves will thank you!
