Why Are My Citronella Plant Leaves Turning Yellow?

Citronella plants, also known as geranium, are a popular choice for gardeners who want to repel mosquitoes and other insects naturally. These plants are known for their distinctive lemony fragrance and are often planted in pots or outdoor gardens.

However, if you notice that your citronella plant leaves turning yellow, it can be concerning. This comes about if you don’t care for your plant correctly. Unfortunately, if you don’t fix the damage early, it can lead to plant rot or death. 

So, what causes Citronella leaves to turn yellow? Yellow leaves can be a sign of various issues, such as overwatering, nutrient deficiencies, improper lighting, pest infestations or disease, low humidity, compacted soil, and poor soil drainage. 

In this article, we will explore some of the common causes of yellowing leaves in citronella plants and some tips for preventing and treating these issues to keep your plant healthy and thriving. 

Causes of Citronella plant leaves turning yellow.

There are various factors that can cause plant leaves to turn yellow. Let’s discuss each and every one of them and the methods you can use to fix them. 

These factors include; 

  • Overwatering
  • Improper lighting
  • Pest infestation
  • Diseases
  • Low humidity 
  • Poor soil drainage


Overwatering is one of the most common causes of citronella plant leaves turning yellow. Citronella grows in well-drained soil. So, when a plant receives too much water, the roots become waterlogged and cannot absorb enough oxygen from the soil. 

This lack of oxygen can cause the roots to rot, preventing the plant from effectively taking up nutrients and water. As a result, it causes the citronella plant leaves to turn yellow, wilting, and eventually die.

In addition to root rot, overwatering can also lead to other issues like fungal growth, which can further damage the plant. 

You can prevent overwatering by watering after the soil is dry. Check the moisture content in the soil before watering. You can check the soil’s moisture level by sticking your finger about an inch into the soil – if it feels dry, it’s time to water. Besides that, purchase a moisture meter to give you the correct moisture content in the soil. 

Also, you can adjust the watering schedule depending on the weather. Give the plant more water during summer and less water during winter. It’s also important to ensure the pot or planting area has good drainage so that excess water can drain away and not accumulate around the roots. 

If the problem persists, check the roots for root rot. If the roots are rotten, remove the plant from the soil, cut off all the affected roots and repot it in fresh soil. After repotting, place it in a bright room with indirect lighting for a week before watering to give it time to heal and use all the existing water. After a week, you can create a watering schedule to prevent overwatering. 

Improper lighting

Improper lighting can also cause citronella leaves to turn yellow. Citronella plants require a certain amount of sunlight to thrive, but too much or too little can cause problems. If your plant is not receiving enough light, its leaves may turn yellow due to chlorophyll deficiency. 

Chlorophyll is the pigment responsible for giving plants their green color, and when a plant is not receiving enough light, it may be unable to produce enough chlorophyll to keep its leaves green.

On the other hand, if your citronella plant receives too much direct sunlight, its leaves may also turn yellow. This can happen because excessive sunlight can cause the plant to lose more water through evaporation, leading to dehydration and stress. As a result, the leaves may become yellow or brown and may even begin to curl or wilt.

To prevent yellowing leaves due to improper lighting, ensure that your citronella plant gets the right amount of light. Citronella plants prefer bright, indirect sunlight, so it is best to place them in a location that receives plenty of sunlight but is shaded by other plants or structures during the hottest parts of the day. 

If you are growing your plant indoors, use grow lights to supplement natural sunlight and ensure that your plant gets the right amount of light. You can purchase the best grow light here. 

Pest infestation

A pest infestation can cause citronella plant leaves turning yellow. For instance, Insects like spider mites, whiteflies, and aphids can suck the sap from the plant’s leaves, which can lead to yellowing, wilting, and stunted growth.

If you notice that citronella has a pest infestation, here is what you should do. One of the first steps is to inspect your plant closely to identify the pests and determine the extent of the infestation. You can then use various methods to control the pests, such as applying insecticidal soap or neem oil, introducing beneficial insects like ladybugs or lacewings, or using physical barriers like sticky traps.

You can prevent your plant from getting infected by pests by keeping it healthy and well-maintained, avoiding overcrowding, and cleaning them regularly. 


Fungi and bacteria cause most diseases that can attack your plant. The diseases affect the plant’s ability to absorb nutrients and water, causing the citronella plant leaves to turn yellow, wilt, and die. 

Fungal and bacteria often causes root rot, leaf spot, and powdery mildew diseases. 

Root rot is a fungal disease that is often caused by overwatering. It can cause the plant’s roots to rot, leading to yellowing leaves and death. Leaf spot is another fungal disease that causes small, circular spots on the leaves, which can then turn yellow and drop off. Powdery mildew is a common fungal disease that appears as a white powdery coating on the plant’s leaves, stems, and flowers. This disease can cause the leaves to turn yellow and eventually die.

To keep your plant from diseases, you need to care for it to keep it healthy and stress-free. Weak and stressed plants are prone to attacks and are easily affected by diseases. Also, once a disease attacks your plant, it is hard to revive the plant. So do your best to keep the plant away from diseases. 

Low humidity 

Citronella plants prefer a humid environment; if the air is too dry, the plant may become stressed and unable to absorb enough water and nutrients. Low humidity can be especially problematic for citronella plants during winter, when indoor heating systems can cause the air to dry excessively. 

Increase the humidity around the plant to prevent yellowing leaves due to low humidity. This can include misting the plant with water, placing a tray of water near the plant, or using a humidifier to add moisture to the air. 

Besides that, ensure that the plant receives enough water, so it doesn’t dry. 

Poor soil drainage

Soil can cause overwatering. For instance, you give the plant the correct amount of water. However, this water remains stagnant in the water. As you continue adding water and none draining out, the soil becomes waterlogged, causing root rot. 

As the roots begin to rot, the plant may become stressed and unable to absorb enough water and nutrients, leading to citronella plant leaves turning yellow and eventually death. Other than yellowing leaves, you may also notice wilting, stunted growth, and a general decline in the plant’s health.

To prevent yellowing leaves from poor soil drainage, ensure your citronella plant is planted in well-draining soil. You can achieve this by adding sand, perlite, or other materials to the soil to improve drainage or by planting the citronella plant in a raised bed or container with adequate drainage holes.

Root bound

Root bound is caused when the roots don’t have enough room in a container. That causes them to stress due to lack of space to spread. The stress eventually affects plant growth, causing the leaves to turn yellow. 

When roots are bound together, they don’t have enough space to spread in search of water and nutrients in the soil. 

You can fix this by repotting the plant in a bigger pot. 

Compacted soil

When soil is compacted, it tends to stop water from passing through. As a result, you will notice water stagnant on top of the soil. You can feel the compacted soil if you stick your finger in the soil. 

Compacted soil makes it harder for the roots to grow or even get enough water to grow. That can result in stress, causing the plant leaves to turn yellow. 

To prevent soil from getting compacted, loosen the soil using a sharp tool. If the soil is too compacted, repot the plant with fresh potting soil. 


When you notice citronella plant leaves turning yellow, don’t panic. Instead, start by determining the cause of the problem to make it easy when fixing. If it’s one of the problems we have stated above, fix it fast before it spreads to other parts of the plant.