Hydrangea Leaves Turning Brown? Here’s Why and How to Fix it!

Hydrangeas are one of the most popular flowering shrubs that gardeners flock to every season, and their popularity continues to grow each year. Their blooms are stunning, and they are relatively low maintenance, requiring only deadheading, occasional pruning, regular watering, and fertilization.

However, these plants are not without their issues. One of the most common problems experienced by both new and seasoned hydrangea gardeners is browning leaves. This discoloration can be caused by several common environmental factors.

If your hydrangea is covered in brown leaves, read on to learn what might be causing the problem and how to fix it.

Transplant Shock

Did you recently plant a new hydrangea, or move one from a spot in your yard to another? Or perhaps you decided to upgrade the pot your hydrangea has been living in? If so, you may have put your plant through a bit of stress. Even perfectly healthy plants can suddenly shrivel and turn brown. The most common reason for this stress is a lack of moisture.

Signs of transplant shock include dried-out, brown hydrangea leaves and wilting flowers. Hydrangeas do not like to dry out. If you’ve planted in less-than-ideal conditions and are seeing these symptoms, it’s quite possible your plant is simply experiencing a bit of transplant shock.

How to Fix

Keep in mind the timing of your transplant. If you are planting in the summer or on a day that’s unexpectedly warm, you’ll want to take a few extra precautions.

Before planting, water the plant thoroughly. This can help prevent transplant shock. If you’ve already planted and didn’t water beforehand, don’t worry—just give it some time and consistent watering. Avoid soaking the plant.

The roots are already under stress, and too much water can lead to rot. Instead, water in small amounts frequently, allowing time for the soil to drain properly.

Fertilizer Burn

Hydrangeas don’t require much in the way of fertilization. They benefit from an application of fertilizer in the spring, but fertilizing during the summer heat can be tricky.

If you apply too much fertilizer—especially when the soil is dry—you risk damaging the plant. One common sign is browning along the edges of the leaves. The leaves may also become dry and crunchy. This is known as fertilizer burn.

Although the damage appears on the leaves, the fertilizer doesn’t need to come into direct contact with them. This type of burn usually starts at the roots, which means the roots may have been damaged as well.

How to Fix

Take a break from fertilizing. Hydrangeas only need two or three applications of fertilizer per year. Using a slow-release formula is a foolproof method—apply it once, and the fertilizer does the work for you.

Once your plant is burned, you can’t reverse the damage, but you can help prevent further injury. Water about once a day to try to flush excess fertilizer from the soil. If you used a granular fertilizer, you may also choose to gently rake the soil surface to remove any remaining granules.

If you’ve found crunchy leaves on your plant, you can leave them as they are or snip them off to improve the plant’s appearance.

Insects

Hydrangeas can experience issues with common garden pests such as aphids, Japanese beetles, and spider mites. The feeding wounds caused by these insects can lead to brown leaves on your hydrangea.

How to Fix

Both aphids and Japanese beetles can be removed by hand. Knock the beetles into a bucket of soapy water, or use a strong spray from your hose to dislodge the aphids. You can also apply soapy water directly to all surfaces of the plant.

In addition to these simple methods, you can use insecticidal soap or neem oil to help eliminate the pests. Be sure to read the application rate information provided on the product label. Using too much of any chemical, including pesticides, can cause additional browning of your hydrangea leaves.

Fungal Diseases

While hydrangeas are tough and resilient plants, they are susceptible to a variety of fungal diseases. These fungal diseases may appear as small brown spots that grow into larger lesions, rust-colored stains, or other visible symptoms.

Most fungal diseases do not cause significant harm to the plant, but they can detract from its overall appearance.

How to Fix

You can help prevent fungal diseases by keeping your garden neat and free of debris. Give your garden a thorough cleanup in both fall and spring, and remove all leaf litter from the ground as well as from within the crown of the plant. These fallen leaves may be harboring fungal spores that can linger and attack in the next growing season.

If you notice symptoms of fungal disease on your leaves, you can use a general fungicide to treat the plant. These products are available at most garden centers. Always follow the instructions on the label of the fungicide you choose. Copper-based fungicides are popular and effective, but overuse can lead to toxicity in the plant.

Removing infected leaves is also an important step, and should be your first line of defense before spraying fungicides. Clip them off and remove them from the garden entirely. Do not compost these leaves, as the fungus can continue to spread.

Insufficient Watering

Hydrangeas have a tendency to droop in the midday sun, then bounce back once the sun shifts and the plants have had some time to recover. However, if this happens repeatedly, you may start to see brown hydrangea leaves that continue to droop. This is the plant’s way of signaling that it needs additional moisture.

How to Fix

This is a simple fix. To quickly remedy this, water your hydrangeas! Water hydrangeas slowly so the plants have time to absorb the moisture. In areas where the soil has become very dry, water tends to run off rather than soak in, which can prevent the plant from rehydrating properly. Simply adding water to dry soil won’t resolve the problem if the moisture isn’t penetrating deeply.

Next, take a look at your watering schedule. If this is a recurring issue, it’s likely time to make some adjustments.

Established plants may need to be watered one to three times per week, depending on your local conditions. These shrubs generally do best with about one inch of water per week. While it may be tempting to spray the leaves, this won’t help with rehydration.

Instead, water the base of the plant slowly, once or twice a day, until the problem resolves. Once the plant has recovered, you can return to a regular watering routine.

Too Much Sun

Panicle hydrangeas love full sun, but the rest of the group really likes partial shade. Partial shade provides about four to six hours of sunlight.

Better yet, choose a planting location that receives sunlight in the morning when temperatures are still cool. If you have a shade-loving variety that gets more than six hours of sun per day, you’re likely to see some scorched or fried leaves.

How to Fix

If your shade-friendly variety is getting fried and crispy, you’ll likely need to transplant it to a shadier location. Look for a spot in your garden that receives light morning sun and offers plenty of space for the hydrangea to grow.

If you don’t have a suitable location in your garden, consider transplanting it into a pot. Choose a container large enough to support the plant’s growth and ensure it gets the water and nutrients it needs. Place the pot on a porch or in a shaded area on your patio.

Alternatively, you can replace the plant with a panicle hydrangea. Panicle varieties thrive in full sun. They are large, make excellent hedges, and produce cone-shaped flowers that typically open white or green and fade to pink as the season progresses.

Excess Wind

Similar to a hydrangea receiving too much sun, wind can draw moisture out of the leaves faster than the roots can absorb more, leaving you with dry, brown hydrangea leaves. This issue is often caused by the plant’s location. Regardless of the variety, it’s important to plan ahead and ensure your hydrangea has plenty of protection from strong winds.

How to Fix

You have a few options. You could transplant your hydrangea to a new location, or you could create a wind barrier using another plant or fencing.

To create a wind barrier, consider planting a small tree or shrub to block the breeze. Reducing wind exposure will help slow the evaporation rate from the leaves. Ornamental grasses, rose of Sharon, or holly bushes are just a few examples of plants that can be used as effective windbreaks.

If you choose to transplant, look for a spot in your garden that offers good protection from both sun and wind. Transplanting is best done in the fall or spring. Be sure to water the plant before removing it from the ground, and water thoroughly after replanting.