Why are Hydrangea Leaves Falling Off?

Hydrangeas display certain signs when their leaves begin to fall off. You might notice leaves turning yellow or brown, wilting, and eventually detaching from the plant. The leaves may also develop spots or appear to be drying out before falling. These symptoms can indicate that the plant is stressed or suffering from a variety of possible issues ranging from environmental factors to diseases.

What are the 7 Causes of Foliage Loss in Hydrangeas?

Hydrangeas can lose their leaves for several reasons, each causing the plants distress in different ways. Here are seven common causes:

• Dehydration: When the plant doesn’t get enough water, its leaves might drop off as a survival tactic.
• Sunburn: Too much direct sunlight can scorch the leaves, leading them to wither and fall.
• Overwatering: Giving the hydrangea more water than it needs can cause root issues, making leaves fall off.
• Frost: Cold temperatures can damage the leaves and make them drop prematurely.
• Transplant Shock: Moving a hydrangea to a new location can stress it, resulting in leaf loss.
• Pests: Bugs like aphids and spider mites suck on leaves, weakening them until they fall off.
• Fungal Disease: Fungi can infect leaves, causing spots, wilting, and eventual leaf drop.

1. Dehydration

The leaves of hydrangeas that are constantly under-watered can turn yellow, become droopy, and fall off.

The soil of your hydrangeas should be kept moist. In heat waves or when hydrangeas are planted in full sun, the soil can quickly become bone dry.

When this happens, hydrangeas can easily lose their foliage because of dehydration.

2. Sunburn

Apart from the dehydration caused by high temperatures, hydrangeas that have been moved outside from indoors without acclimation or hydrangeas that don’t tolerate full sun can lose their leaves because of too much sun.

While some hydrangeas do enjoy full sun, especially in cooler climates, ideally, they should not be exposed to hot, burning sunlight.

Hydrangeas losing their leaves because of sunburn is especially common in hydrangeas that have been grown indoors. The sudden exposure to direct sunlight can have this effect on hydrangeas.

3. Overwatering

It’s not just dehydration that’s to blame for leaves falling off your hydrangea. Sometimes it’s the opposite that causes trouble — overwatering.

When constantly overwatered or if planted in soil with poor drainage, a hydrangea’s roots may start to rot, cutting off the supply of nutrients to leaves and blooms.

While you should not allow the soil of hydrangeas to completely dry off, you should also not let it sit in water.

4. Frost

If you’ve transplanted a hydrangea to the garden in early spring, a late frost can cause the plant to lose its leaves and buds.

This is why it’s important to transplant hydrangeas only when they’re dormant or when there’s no chance of a late frost damaging new growths.

5. Transplant shock

If you’re transplanting hydrangeas in mid-spring or summer, transplant shock can also cause leaf loss and even bloom loss.

This is one of the reasons why it’s best to schedule any transplanting or hydrangea planting to when the plant is dormant.

6. Pests

Hydrangeas aren’t prone to pest problems as much as other garden plants, but when under siege from certain pests such as aphids or spider mites, hydrangeas can lose their leaves if the infestation is serious enough and it’s left unchecked.

7. Fungal diseases

Some hydrangea fungal diseases can also result in leaf loss if it’s untreated. Fungal diseases are notoriously easier to prevent than to treat, so make sure you follow my disease prevention tips.

These are the most common reasons why hydrangea leaves fall off. Now let’s see what you can do to prevent these.

How to Care for Hydrangeas to Avoid Leaves from Falling Off?

Caring for Hydrangeas means giving them what they need to stay healthy and keep their leaves.

• Water them correctly. Hydrangeas like moist soil but not too wet. Check that the top inch of the soil is dry before watering.
• Place them in the right spot. They need morning sun and afternoon shade to thrive.
• Use mulch. This helps the soil keep moisture and stay cool.
• Prune carefully. Remove only dead branches and leaves to let the healthy parts grow well.
• Feed them right. Give them fertilizer that’s made for hydrangeas to get the right nutrients.
• Protect them from frost. Cover them or bring them inside if it gets too cold.
• Check for bugs and disease. Treat them quickly if you find any problems.

Following these steps helps the hydrangeas stay strong and hold onto their leaves.

How Do Seasonal Changes Affect Leaves on Hydrangeas?

Seasonal changes can make hydrangea leaves act differently throughout the year. As seasons change, so do the temperatures and the amount of sunlight plants get.

In spring, new leaves grow because the weather is getting warmer and there is more sun. Summer might stress a hydrangea if it gets too hot or does not have enough water, causing leaves to droop or fall.

In fall, hydrangea leaves can change color and fall off naturally as the plant gets ready for winter. Colder weather in winter can make a hydrangea lose its leaves and go dormant to save energy.