5 Reasons Why My Hydrangea Leaves Are Yellow

Hydrangea Leaves Are Yellow

Have you ever had an experience where your hydrangea leaves are yellow? It’s not an experience gardeners want, especially for this plant. However, if you haven’t had this experience and notice the hydrangea leaves turning yellow, you need to find the cause immediately. 

Sometimes you think you have a perfect plant growing in your garden; the next minute, it has yellow leaves. Where do you start from then? Prevention is better than cure in all circumstances, including caring for your plant. 

After noticing the yellow leaves, you don’t know where to start because you don’t know what is causing the problem. So, what causes hydrangea leaves to turn yellow? Your hydrangea leaves are yellow due to lack of nutrients, diseases, Improper watering, poor lighting conditions, sudden change in temperatures, and soil quality. 

This article will explain how these factors cause your plant leaves to turn yellow. Read to the end to find out the root cause of the problem.

The reasons why my hydrangea leaves are yellow

Hydrangea Leaves Are Yellow

Before we look at the reasons, first, you must understand that there are many shades of yellow when the plant has a problem. To identify the problem, you have to know the type of yellow your leaves have, and then you can determine the problem. 

Yellowing types

  1. Leaves turn yellow completely — This is the most common symptom, and you can notice it because the whole leaf is yellow. Once this happens to your leaf, it is ready to die. This problem can result from overwatering, low temperature, low humidity, or lack of nutrients. 
  1. Yellow leaves with green veins —- When part of the hydrangea leaves are yellow, it usually means the plant changed its color due to chlorosis. This problem starts due to a lack of nutrients such as iron. It is easy to solve by adding iron to the soil. 
  1. The leaves edges are yellow —- When the edges are yellow, it means the plant lacks enough nutrients to feed the plant, and as a result, some parts are not receiving the required nutrients. You can solve this problem by adding nitrogen fertilizer that contains iron.  
  1. The leaves are yellow at the bottom —- When this happens, it’s a sign of aging of the hydrangea plant. The leaves turn yellow at the bottom, then die and fall off. 

Let’s look at the causes of yellow leaves on hydrangeas leaves

Improper watering 

When we talk about watering, two ways can result in yellow leaves in your plant. That is overwatering and underwatering. 


Overwatering gives the plant more water than it requires to grow. It happens when gardeners don’t know the amount of water to provide the hydrangea plant. It grows in well-draining soil. So, you don’t have to worry if your soil drains off the water well. However, adding water can result in soggy or wet soil if you have poorly draining soil. 

When you overwater, the water remains stagnant at the top, blocking the spaces within the soil. Once these spaces are blocked, the roots can’t breathe, which causes them stress. The stress starts to show by hydrangea leaves turning yellow. If this continues for some time, fungi will grow, affecting the roots that begin to rot, resulting in the leaves turning completely yellow. After some time, they will wilt and die. 

To solve this problem, check the soil to see if it is wet. The plant requires moist soil, not wet or soggy. You can check by using the finger test or purchase a moisture meter to determine moisture content in the soil. 

If the soil is wet, leave it to dry before you water it. Ensure that you water only after the soil is dry. And if the roots have been affected, remove them from the pot, let them dry and repot them with fresh soil after cutting off the affected roots and leaves. 


Underwatering happens when you give the plant less water due to a poor watering schedule. For instance, you neglect your plant for a week without watering it. It might not be severe, like overwatering, but it also causes wilting, leaves turn yellow, and the plant starts drooping. 

When it happens, you will notice the tips and edges turning yellow, and the whole leaves will turn yellow after some time. 

To solve this problem, give your plant water at least twice daily, in the morning and evening. Or you can add mulch to the plant to improve moisture retention as you reduce watering times. 

Lack of nutrients 

Nutrients such as iron and nitrogen are essential in the growth of the hydrangeas plants. When the hydrangea leaves are yellow, this can be a problem. It starts with parts of the hydrangea leaves turning yellow. 

The plant is a heavy feeder, so it requires nutrients frequently. To improve its quality, you need to add compost or organic matter to the soil. But, if you have been feeding your soil and it has the same problem, test the pH and nutrient levels. The best time to test the soil is in early spring. You can purchase a soil test kit to know what the plant needs.  

To solve this problem, add nitrogen-containing fertilizer in the spring period to improve the growth of green leaves. Add a fertilizer containing nitrogen, phosphorus, or potassium in the summer to encourage flowering. And in the fall, add a fertilizer with a potassium-phosphorous mixture to prepare the plant for winter. 

If the plant lacks iron, You can purchase a Chelated iron solution and add it to the soil.  

Lack of sunlight

Hydrangeas plant grows well in partial sun. However, some gardeners place the plant in a dark area or direct sunlight. Place the plant in a room with bright indirect sunlight is the best for your plant. 

These can cause the hydrangea leaves to turn yellow. The hot sun can scorch the leaves,  resulting in them dying. 

To solve this, place the plant in a shaded area that receives the morning sun and an evening shade. About 4 to 6 hours of sunlight are enough to grow hydrangea plants. 


When diseases start to attack your hydrangeas plant, it is prone to damage that lowers the immune system. It will result in hydrangea leaves turning yellow. Some of the diseases include chlorosis and gray rot. 

Chlorosis causes discoloring in the leaves, which appears when the plant lacks nutrients. You can fix it by adding nutrients like iron and nitrogen into the soil. Prepare a solution using 30ml potassium nitrate and mix it with 10L water. Water the soil with that solution once a week for 30 days. 

A fungal infection causes gray rot. You will notice it when the plant starts to turn black and then curls and crumbles. As soon as it starts to turn black, begin fixing the problem. Use a fungicide to remove the disease. 


If you have noticed that your hydrangea leaves are yellow, you are doing something wrong with your plant. But, it is possible to have green leaves. The best way to achieve this is to care for it and ensure it is healthy. 

Ignoring the tiny yellow spot on the leaves can cause more problems than you can imagine. As soon as the color changes, start finding the problem and the possible solution. It can save you from future pain, like throwing away a dead plant.