How to Identify and Treat Hydrangea Diseases | Gardener's Path

There are few things more beautiful than lush hydrangea bushes. Unfortunately, their beauty can be sullied by a number of fungal and viral diseases (and two bacterial diseases).

However, there are steps you can take to keep your beauteous shrubs from falling victim to one of these diseases.

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We will introduce you to the major hydrangea diseases, so you know what to look for and how to prevent and treat them.

This fungus can severely affect the flower buds and even kill them before they open. In addition, infected flower parts can fall on the leaves and infect them.

The first symptoms are water-soaked spots on the flowers. However, these grow into reddish brown lesions.

Botrytis is more likely to be a problem under cool and damp conditions, such as several days of cloudy, humid, and rainy weather.

You can take steps to try and prevent this infection. Keep the humidity low. Don’t water late in the day, and only water at the roots, so you don’t get the flowers and leaves wet.

If you can, keep good airflow around your plants. Space them properly, and prune branches that are closely spaced. Treat your pruning shears with bleach as you prune, so you don’t accidentally spread any disease.

Also remove dead or damaged flowers and leaves to prevent the fungus from gaining egress into the plant. Clean up debris around the plant, so that Botrytis can’t live on the dead tissue.

If you have a persistent problem, you may need to use fungicides. Options include iprodione, or thiophanate-methyl.