Why are Philodendron Leaves Turning Yellow? 4 Ways to Fix Them

Healthy philodendron leaves are green with exotic beauty. The plant helps purify indoor air with the big healthy leaves, but when they turn yellow, it’s a sign that something is wrong.

Philodendron leaves turn yellow due to overwatering, underwatering, nutrient deficiency, or poor lighting conditions. To fix the yellow leaves, move the plant to a spot with bright indirect light, apply fertilizer, and then water 1-2 times per week, but only when the top inch of the soil is dry.

A change of color (chlorosis) from green to yellow indicates that there could be a problem affecting the plant. Common reasons for yellowing include water, nutrition, or lighting. Excess or inadequate lighting can cause leaves to droop, change color and drop to the ground.

Why are philodendron leaves turning yellow?

Yellowing leaves indicate that your plant is sick and needs special attention to recover. Several issues can cause the plant’s leaves to change color; some are easier to deal with than others.

For example, leaf discoloration can result from poor water quality the plant is suffering from. Saltwater can cause chlorosis and other complications.

Here’s why philodendron leaves are turning yellow:

Poor light conditions

Philodendrons require medium levels of sunlight to grow. When growing indoors, the plants prefer bright indirect light. Exposing your plant to direct sunlight can cause yellow spots that darken over time to form black patches. The damage is more pronounced on the surface in constant contact with the sun’s rays. Damage might also occur if you place the plant too close to heating vents, air conditioners, etc.

Insufficient sunlight can also lead to the yellowing of the philodendron leaves. Although philodendrons can grow in poorly lit areas, low sunlight causes the leaves to turn yellow on the tips. The affected leaves can dry out and drop to the ground if the damage is too severe.

Nutrient deficiency

Yellowing leaves can occur as a sign of chlorosis that’s caused by iron and magnesium deficiency. Iron is important for the greening of foliage. Other minerals such as zinc, magnesium, and calcium are also essential for healthy leaf development in plants.

A plant that has yellowing leaves might indicate little nutritional value in the soil. The soil may lose its nutritional value due to leaching, which is why plants cannot absorb these nutrients.

For example, if you notice V-shaped yellow spots on its leaf surface, your plant is most likely suffering from inadequate amounts of magnesium. The problem is relatively easy to correct, but only if you know what to look for.

Root rot

Philodendrons are not prone to many ailments. They are solid and hardy plants that can survive in different conditions and thrive.

Root rot is a fungus disease that damages the roots and therefore affects the plant’s ability to absorb water and nutrients, causing the yellowing of leaves. A common reason for root rot is overwatering, pests, and fungi.

If you notice your plant’s leaves turning to yellow, then brown, but remain attached to the plant, you could be dealing with a fungi infestation in the soil.

The pythium fungus attacks plant roots and causes them to become black, wet, and mushy. The fungi also affect a root’s quality by creating spaces within its inner structure. If you take an infected root, you might notice how easy it is to separate the cortex and outer layers from the core of the roots.

Fungi are much more complicated to deal with. They attack the hard-to-reach areas of your plant, such as the roots. Fungi such as Anthracnose and Southern blight can cause leaves to droop, turn brown and dry if you don’t control them quickly.

Pest infestation

Philodendrons are vulnerable to pest attacks which might cause the leaves to turn yellow. Pests such as aphids will attach themselves on sensitive surfaces such as under the leaves and stems to feed on the plant’s sap. Spots of discoloration on the philodendron could indicate that the plant is suffering from pest damage.

Overwatering or underwatering

Overwatering your philodendrons can cause leaves to turn yellow. Philodendrons require minor amounts of water and prefer growing on well-drained soil to get rid of excess water quickly.

An overwatered philodendron has soft squishy leaves that change to yellow because excessive water affects photosynthesis. You might also notice the plant becomes weaker with brown spots and stunted growth.

Too much water clogs the roots and reduces their ability to take in oxygen. The wet soil also provides a suitable environment for fungi and other microorganisms to grow. You can tell if your plant is overwatered by looking at its leaves.

Underwatering can also cause the yellowing of the plant’s leaves. Common indicators of an underwatered philodendron include dry soil, wilting and curling of leaves that later turn brown and drop off.

Natural yellowing and shedding

Philodendrons shed old leaves for newer, younger ones to grow. You might observe your plant’s leaves unexpectedly start to change color to yellow. It could be that the plant is experiencing a regenerative phase where new leaves are growing to replace the older ones.

Such plants remain relatively healthy and revert to their normal green color after the old leaves fall off.

How to fix yellowing philodendron leaves

You can fix yellowing philodendron leaves by maintaining a good care routine that meets the plant’s growing requirements. It’s never advisable to cut off a plant’s leaves unless the damage is too severe or there’s a possibility of infecting other leaves within the plant.

Here’s how to fix yellow philodendron leaves:

1. Water the plant 1-2 times a week

Philodendrons require minimal amounts of water periodically. A proper growing medium for the plant should be moist but not wet. Water philodendrons 1-2 times a week while letting the top 2 inches of soil to dry between waterings.

Here are tips to help you water philodendrons correctly and fix yellowing leaves:

• Push your finger about 2 inches under the soil surface to test the moisture level. Moist soil indicates that the plant can go for a few more more days without additional water. If the soil is dry,it is time to water the philodendron.
• Gently pour water near the plant’s base until it trickles down the drainage hole.
• Allow the top two inches of the medium to dry out before watering your plant again.
• Mist the leaves twice a week with minimal amounts of water to create a microclimate within the plant

The amount of water and frequency varies depending on year, temperature and the potting medium’s retention capacity.

2. Provide bright indirect light

Philodendrons can tolerate low light conditions but yellowing leaves could be a sign the light is insufficient. The plant prefers medium light to bright indirect sunlight.

Move your philodendron away from direct sunlight. You can add blinds on your windows to regulate the amount of sunlight reaching your plants.

Move the plant close to a window or door that receives indirect sunlight to fix the poor lighting that’s causing the yellowing leaves. Philodendrons don’t require much sunlight, so that gives you plenty of options on where you think is best to place your plant.

3. Feed the plant with fertilizer

A nutritious potting medium promotes plant health and prevents your leaves from turning yellow. If you suspect that your plant’s leaves are changing color due to poor nutrition, there are several options you can consider.

First, feed the plant with an iron supplement such as Ironite to fix iron deficiency that’s causing leaf chlorosis. To add magnesium to the soil, mix 1 teaspoon of magnesium sulfate or Epsom salts per 1 gallon of water and enrich the soil with it.

Second, remove the plant from the pot and replant it with a new, more fertile potting mix. Be gentle not to damage the roots in the process. You can also try adding fertilizer to the soil to fix nutrient deficiency that’s causing the yellowing leaves.

Here is a proper way to add fertilizer to your plant.

• Take a sample of the soil to the lab and identify which essential nutrients are missing.
•  Purchase the fertilizer with the recommended nutrient amounts and mix it with the soil.

4. Treat fungal diseases and pests

Fungi pose a much more significant threat and are much harder to deal with. The best way to fix yellow philodendron leaves is to change the potting mix and discard the infected growing medium.

When repotting, prune off any infected roots beyond saving (in the case of root rot).

Here’s how to rid diseased roots from your plant:

• Soak the soil in water about 30 minutes prior.
• Gently tap on the sides of the potting container to loosen the soil from the roots.
• Gently tug the roots by holding on to the stem of the plant
• Was the plant’s roots and removed any that look black, rotten or unhealthy
• Transplant your philodendron on a sanitized pot with a new medium.

Spray a mild homemade insecticide such as vinegar when dealing with visible pests such as aphids and other insects. You can also tend to your plants and physically pick off the bugs from the surfaces.

Prevention

You can prevent the yellowing of your plants through regular maintenance and observation. Always avoid overwatering your plants and only do so when your plant needs water.

In case you accidentally overwater the plant, leave it to the sun for a few minutes for the excess water to dry off.

Some potting sizes might be too big such that the plant becomes vulnerable to overwatering and encroachment by bacteria, fungi, and unhealthy soil insects.

Always grow your plant in an ideal lighting space with sufficient airflow and away from hot, warm objects to prevent leaves from turning yellow and falling off.

Lastly, maintain a temperature range between 55°F to 90°F for optimal growth of your philodendrons.

References

• Sandra Mason 08/28/2007, University Of Illinois: Yellow Leaves Can Indicate Plant Problems
• J. J. McRitchie, July-August 1992, Magnesium Deficiency of Foliage Plants