Hydrangea Leaves Turning Red – Reasons and Solutions

Hydrangea is a flowering plant that thrives in shady, humid environments. This type of environment makes the leaves turn a rich dark green. But, if the conditions are optimal for red coloration (bright light and dry air), the leaves will change and grow red.

Hydrangeas thrive in sunny and hot weather, making it difficult to grow healthy roots before they reach maturity. But, with optimal conditions, they can be grown as houseplants and bloom beautifully indoors.

Hydrangeas are one of the most popular flowering plants for flower gardens. People enjoy them for their attractive blooms in beautiful shades of pink, white, blue, and red. The leaves of Hydrangea are also quite attractive and often used in floral arrangements because of their varying shades of green color. Some varieties of Hydrangea also have reddish-colored veins on their green leaves.

Hydrangeas leaves are thin and large compared to other flowering plants. The leaf veins are a prominent feature in Hydrangeas that is evident from any distance.

The leaves of a hydrangea plant turn red color when the plant is exposed to sunlight for long periods. Exposing the hydrangea leaves to direct sunlight stimulates them to produce anthocyanin pigments, resulting in reddish coloration on the leaves top and bottom edges.

Causes of Hydrangea Leaves Turning Red

There are several reasons why Hydrangea leaves turn red. The following are the common causes of red coloration on Hydrangea leaves:

  • Extreme cold weather conditions
    The color change of Hydrangeas leaves occurs when exposed to cold winter weather. The leaves turn red color when exposed to cool temperatures for long periods. They are deciduous plants; hence the leaves shed when the temperatures are too cold. Its leaves will regrow and turn back to their normal green coloration once the weather conditions are warmer.

  • Weak sunlight exposure
    The red color of Hydrangeas is also due to darkness and lack of adequate sunlight for the plant leaves. They need direct sunlight during the morning hours and some hours of direct sunlight in the afternoon.

    Inadequate sunlight results in the coloration of Hydrangea leaves turning reddish due to its inability to produce enough anthocyanin pigments necessary for its survival during winter. The color of the Hydrangeas will turn darker because of the lack of light. The plant needs a few hours of sunlight exposure to survive and thrive during winter.

  • Under watering
    Hydrangea leaves turning reddish can also be caused by underwatering. The coloration of the leaves is due to wilting and lack of hydration and nutrients absorbed from the soil.
    Direct sunlight in the afternoon activates the roots of Hydrangea plants, absorbing water from the soil. If under-watered, they will turn reddish because they lack nutrients and water absorption capacity.

    Under watering also results in wilting, making the leaves turn red because they cannot absorb the sunlight required to thrive during winter. It causes the leaves to turn brown and wilt. Hydrangea comes from the Greek word “Hydra,” meaning water, and “Gena,” meaning leaf.

  • Over watering
    The color of Hydrangea leaves turning red can also be due to overwatering the plant. It might be a difficult balance task since the plant needs a lot of moisture to thrive; however, too much can also be problematic.

    Hydrangeas have large leaves and hence root systems as well. If over-watered, the leaves will turn reddish due to their inability to absorb water and nutrients. The leaves will also begin to rot when overwatered.

    Over watering causes the roots and soil of the Hydrangea plants to lose oxygen and vital nutrients for survival. It also grows mold on the leaves if overwatered and leads to the infection of the plant. Heavy rains during winter can also cause overwatering and reddish coloration on Hydrangea leaves.

  • The presence of sunlight
    Hydrangeas require sunlight to produce attractive flowers. Therefore, you should always plant them in a place exposed to sunlight for most of the day. Hydrangeas should not be placed in dark corners or where it does not receive sunlight. Exposure to direct sunlight for long periods will result in reddish coloration of Hydrangea leaves. Too much exposure burns the leaves and turns them brown and red.

  • Low humidity conditions
    The color change of the leaves of Hydrangeas occurs when it is exposed to low humidity levels during winter or spring. They are deciduous plants, so for them to survive and bloom, they require lots of moisture.

    The leaves of Hydrangea are covered with wax. The wax will become brittle and reddish if the leaves have low moisture levels. High humidity levels in the air will prevent the leaves from turning reddish.

  • Ripping
    Ripping the Hydrangea stems can also cause the leaves of a plant to turn red. Ripping or cutting the stems of hydrangeas can induce photosynthesis, increasing its need for water, fertilizer, and other nutrients that may not be available in its root system. It will also weaken the stems of hydrangeas which can result in reddish coloration of the leaves.

    It is important to note that ripping the stems is only beneficial for cutting flowers and not for growing plants.

  • Stress on the plant
    Stress on a plant can also cause the reddish coloration of its leaves. If a plant is transplanted, it will experience stress that may cause leaves to turn redder.

    It is important to follow a well-designed system to overcome the stress that may result in the reddish coloration of the leaves. Drought should be avoided when transplanting the plant and provide an optimal environment for the plant to flourish. Hydrangeas are very sensitive plants, especially during transplantation, where they are exposed to various infectious diseases.

  • Insect infestation
    The color of Hydrangea leaves turning red is due to insects feeding on it. It is common for insects to feed on the leaves of plants. They are attracted to the phloem tissue (feeding site) and cause damage to the vascular system that may result in reddish coloration of the leaves.

    Pest infestation is not uncommon, especially when they are exposed to direct sunlight and not shaded by trees. Insects also tend to hide in dark corners or areas where there is no sunlight at all. Insects will also come from outside and crawl inside the hole in the soil where the plants are placed. They may lay their eggs in such places.

  • Lack of appropriate pruning
    Pruning is an important activity that requires you to be precise. It involves cutting off your plant’s dead and dried-out hydrangea leaves. For Hydrangea, it’s best to do pruning in late fall so the cuts can heal up in early spring when they produce new leaves. Pruning in late fall will give the plant enough time to regrow its leaves before spring arrives.

    Improper pruning will ruin the plant and make it weak. It may also cause the leaves to turn red. Picking pruning is an important activity. While there are many ways to determine whether or not you have picked the correct Hydrangea, you may try asking your hydrangea vendor for some tips on when and how to prune your plant.

  • Phosphorus Deficiency
    The leaves of Hydrangea may turn red if they have a deficiency in Phosphorus and Potassium fertilizer. It is important to have these nutrients when growing hydrangeas because it is crucial to helping the growth of these nutrients. A lack of phosphorus and Potassium will cause reddish coloration to the leaves.

    – Hydrangea plants are susceptible to spider mites, scale insects, and other fungal diseases. When the leaves begin to color red, these kinds of diseases are spreading. These pests are like a magnet for aphids, mites, and whiteflies that swarm inside the plant once they emerge.

    – These pests feed on hydrangea leaves by sucking their juices without damaging their cellular membrane. They also cause reddish coloration of the leaves when they are present in large numbers, especially during the early stages of disease suppression.

    – While feeding, they may spread the infection to other parts of the plant. Therefore, it is important to prevent them from infesting your hydrangea plant. You can minimize the occurrence of these pests by limiting their access to the plant through proper warding and keeping them away from the plant during periods of high humidity.

    – Remember that spider mites will also cause reddish coloration of the leaves when present in large numbers.

Solutions for Hydrangea Leaves Turning Red

  • Prune the plant
    The easiest way to recover from the reddish coloration of the leaves is to prune your Hydrangea plant. Pruning helps stimulates new growth and allows the replacement of damaged leaves. Ensure you know How to Trim a Hydrangea correctly to prevent further damage to its leaves and stems.

  • Change the location of your plant
    If your plant is being over-exposed to harsh sunlight and temperature variations, it may develop a reddish coloration. You can change the location of your plant to prevent it from getting a reddened appearance. It is advisable to place your plant in a place that is shaded by trees or walls.

  • Move the plant away from the window
    Plants tend to absorb sunlight, especially when they are near windows. They may develop reddish coloration due to too much exposure to ultraviolet light. Move your Hydrangea away from the window and ensure it receives medium sunlight.

  • Increase the amount of fertilizer
    Once you have pruned your Hydrangea, fertilizing it will help to promote new growth and disease recovery. You can use Phosphorus and Potassium fertilizer to encourage new growth and recovery.

  • Remove the diseased plants
    Removing a diseased plant will help prevent the further spread of the disease to other plants in your garden. You should remove all infected plants from your garden to stop the spread of infection. Removing sick plants will prevent the further spread of disease to other plants.

  • Restrict the entry of pests
    To keep your hydrangea disease free, you can use a mulch to block the entry of pests into your garden. You can also use wire or string mesh that is small enough to keep out pests but big enough for air and water to get through. It will also be a good idea to eliminate weeds that harbor pests.

  • Foliar spray the plant with insecticide
    Foliar spraying will help kill off any pests on your plant. It is important to ensure you discover which pests are infesting your plant. You can then use the appropriate insecticide for each type of pest. While spraying, you should use a weak solution to minimize the risk of affecting other plants.

  • Foliar spray the plant with fungicide
    Foliar spraying can also be used to kill off fungal infections. It is important to use a fungicide with an active ingredient that is effective for the fungus that infests your Hydrangea. It is best to use a fungicide for the fungal disease present on your plant.

  • Give your plant enough water
    Regularly watering your Hydrangea helps reduce the occurrence of fungal diseases and the effect of weather conditions. To prevent fungal diseases, one should water their Hydrangea in a drip system rather than applying large amounts of water at once as it may cause fungal disease to spread. Fertilize your plant with water-soluble plant food that is rich in nitrogen.

  • Foliar spray the plant with Nematicide
    Foliar spraying with Nematicide effectively controls nematodes that feed on the roots of Hydrangea plants. When used in conjunction with other methods, it can reduce the reddish coloration of leaves. Nematodes are small worms that feed on plant roots and stunt the growth of plants.


While Hydrangea plants may turn red coloration during periods of high humidity, it is important to note that this will not affect their beauty.

Although the flowers may turn red, the effects of this on the plant are temporary. These only indicate that your plant suffers from fungal infection and other diseases. If it won’t affect your plant’s growth or appearance, then there’s no cause for concern because you did nothing to harm your Hydrangea.

These fungal infections and diseases can easily be controlled when they start to show themselves. It is when they become severe that it is important to seek the help of a professional gardener.

Hydrangea plants are commonly sold at nurseries, garden centers, and other places that deal with plants. It is best to find a nursery you are familiar with to have the best service and quality products for your Hydrangea. A healthy Hydrangea plant is fun to look at, but deteriorating leaves may lead to other problems.

If you can find a good hydrangea plant at a reasonable price, you can expect that it will live many years with minimal care. Hydrangeas are one of the easiest and most forgiving species for use in home orchards.