12 Reasons your Orchid Leaves are Turning Yellow (and How to Fix Them)

If your orchids lovely green leaves have started to turn yellow (or already have) it’s both disappointing and worrying. Is your orchid dying and can it be saved?

Understanding what’s causing the discoloration is the only way to fix what’s wrong and make sure it doesn’t happen again.

So let’s take a look at the most common causes of yellowing leaves and how to deal with them.

Video: Why Orchid Leaves Turn Yellow

1. Natural Aging Process

Just like everything that’s alive orchids will age. When they do the oldest leaves, that you will usually find at the base, turn yellow and eventually drop off.

This is your orchids way of saving energy and sending its nutrients to the newer growth.

Identifying Natural Leaf Shedding

• Yellowing happens in the oldest leaves at the base.
• The rest of the plant stays healthy and doing well.
• No signs of pests or diseases are present.

What to Do

If it’s only the leaves at the bottom that are turning yellow and the rest of the plant is healthy then don’t be worried. Just let the leaves fall off as part of the natural growth cycle.

2. Overwatering

Overwatering is probably the most common reason orchid leaves turn yellow. They don’t like too much water and rather have their roots dry out between each time

Having roots that are constantly wet can suffocate the plant and will rot. This eventually leads to the plant not being able to take up the nutrients it needs and this causes yellow leaves.

Signs of Overwatering

• Lowest leaves turning yellow.
• Mushy or black roots.
• A musty or sour smell from the potting medium.

How to Correct

• The potting medium should be dry before you water. Check it by touching to see.
• Make sure the pot has enough drainage holes.
• Think about repotting the orchid into fresh medium that drains well if you find root rot.

3. Underwatering

Not enough water will also cause the leaves to turn yellow too. When an orchid is dehydrated it can’t transport the nutrients properly and this stresses it as well as causing the leaves to become yellow.

Signs of Underwatering

• Wrinkled or shriveled leaves.
• Dry, brittle roots.
• The leaf tips turning yellow first.

Remedy

• Water your orchid consistently and make sure the potting medium is fully wet through.
• Keep a close eye on your orchid and react to how it’s doing with more or less water depending on it’s health.

For more help see our orchid watering guide to know how to, when to and how often to water your orchid.

4. Not Enough Light

Much like watering too ouch and too little can have a big impact on your orchid. Getting either wrong will cause yellowing leaves.

Too Little Light

Orchids need bright, indirect light. If they’re not getting enough they don’t photosynthesize properly and this will cause pale or yellow leaves.

Too Much Light

Too much light will burn the leaves. They will either turn yellow or develop sunburn spots, which don’t look great!

Best Light Conditions

• Put your orchid near east or north facing windows.
• Use a sheer curtain to diffuse any direct sunlight.
• Move the plant and roster it from time to time so it gets an even amount of light all over it.

5. Temperature Stress

Orchids are sensitive to temperatures that fluctuate a lot. If they spend too long in temperatures, both hot and cold, that are too extreme for them then it may lead to yellow leaves.

Preferred Temperature Range

Most orchids do best in temperatures between 65°F to 80°F (18°C to 27°C) during the day and slightly cooler at night.

Signs of Temperature Stress

• Yellowing leaves.
• Drooping or limp leaves.
• Not blooming and dropping buds.

Preventive Measures

• Keep your orchid away from drafts, heaters and air conditioners.
• Don’t put yours in windows that are likely to get fluctuating or extreme temperatures.

6. Nutrient Deficiencies

Orchids don’t need a lot of feeding but they like certain nutrients to keep their foliage healthy. A lack of these nutrients can lead to yellowing leaves.

Common Nutrient Deficiencies

Addressing Nutrient Deficiencies

• Use a balanced orchid fertilizer.
• The fertilizer should be diluted to half the recommended strength so it doesn’t “burn” the roots.
• Feed your orchid regularly during the growing season (spring and summer) and reduce how much you do during dormancy (fall and winter).

7. Potting Mix Breakdown

Over time the potting medium of your orchid will break down and hold on to too much moisture. This will end up with the roots being suffocated, stopping the air from flowing well and causing the leaves to turn yellow.

Signs Your Potting Mix Needs Replacing

• The potting mix is compacted and doesn’t drain properly.
• You notice a sour or musty smell, which is usually a sign of decaying matter.
• The roots are dark or mushy when you take your orchid out of it’s pot.

How to Repot Your Orchid

• Use a potting mix that drains well and has perlite, bark or charcoal in it.
• Take the orchid out of it its old pot, trimming away any decaying roots.
• Repot in a clean pot with a good amount of drainage holes that will let the roots breathe.

For more help try our simple guide to repotting an orchid (with easy steps)

8. Pests and Diseases

Pests and fungal or bacterial infections can also cause yellowing leaves. Pests aren’t a major problem for orchids but they can still be affected by a few of them.

Common Orchid Pests

Dealing with Pest Infestations

• Wipe the leaves with a mix of water and soap to get rid of the pests.
• Use a cotton swab dipped in rubbing alcohol to dab individual pests you can see.
• If you’ve got a bigger outbreak then you might want to try a neem oil solution or insecticidal soap.

For more help see our guide to orchid pests and the best ways to get rid of them.

Fungal and Bacterial Infections

You get fungus or bacteria when your orchid either gets too moist or not enough air. Look for dark, sunken spots or areas of rot which can cause leaves to turn yellow.

Treating Infections

• Remove the plants that affected first so it doesn’t spread any of the fungus/bacteria.
• Trim away any affected leaves.
• Apply a fungicide or bactericide.

9. Water Quality

What type of water you’re using to water your orchids can have a surprisingly large effect on its health. Orchids are sensitive to some minerals and chemicals that you find in most tap water. These can build up in the potting medium and cause yellowing leaves over time.

Recognizing Water-Related Yellowing

• Leaves turn yellow but show no other signs of overwatering or underwatering.
• Leaf tips or edges turn brown or crispy.

Improving Water Quality

• Use rainwater, distilled water or filtered water whenever possible.
• Flush out the potting medium every month to get rid of any minerals that have built up in it.
• Don’t use softened water as it contains high levels of salt.

10. Root Health

Healthy roots are, like with most plants, very important. The roots take up the nutrients and water.

Yellow leaves can be a major sign of poor roots, which often come from overwatering, underwatering or decaying potting medium.

Inspecting Root Health

• Healthy orchid roots will look firm and white or light green when moist.
• Look for any mushy, dark or nasty smelling roots as any of these is a sign of rot.

Reviving Poor Roots

• Remove the orchid from its pot and trim any dead or decayed roots.
• Repot in fresh medium and water sparingly until your start to get new growth.
• If your orchid is severely affected then try putting it in a clear pot that has moist sphagnum moss in it as it will encourage the roots to regrow.

11. Environmental Stressors

Orchids are quite sensitive to any changes in their environment. If they get stressed from a suddenly change the in their usual conditions it can result in yellow leaves.

The most common stressors are moving your orchid, changing how much light it gets or fluctuations in the humidity.

Reducing Environmental Stress

• Gradually acclimate orchids to new locations by moving them slowly into new lighting.
• Keep the humidity levels stable. They should be between 40-60% around your orchid.
• Simply try to not move your orchid too much. The less you do it the less chance you have of it being stressed.

12. Humidity Levels

Orchids like higher humidity. Very dry air can lead to stress and yellowing leaves.

Ideal Humidity

• Most orchids do best in humidity levels between 40 to 60%.
• If the humidity is too low or too high it can have a big impact on how healthy the leaves look.

Maintaining Humidity

• Use a humidity tray or a humidifier near your orchids.
• Mist the leaves a little in the morning as you don’t want the water to be left sitting on the leaves throughout the night.
• Group any of your plants together as they can increase the humidity for each other.

Final Thoughts

Yellowing leaves on orchids aren’t always a disaster – so don’t panic. But it is usually a signal that something is off.

Hopefully these 12 potential causes have helped you to figure out what’s going wrong and how you can change what you’re doing to make your orchid happy again.