Should I spray my tree with fungicide?

Usually, good sanitation and pruning are enough. Fungicides are rarely needed unless the infection is severe and recurring every year.

Will these spots kill my magnolia?

Leaf spot is rarely fatal, but it can weaken the tree if it happens every season. Focus on improving airflow to help the tree recover.

Star magnolia: spots, causes and fixes

Check these first

Inspect the leaves for fuzzy growth or distinct borders around the spots.
Check if the spots are appearing mostly on the lower, inner branches.
Look at the weather patterns over the last two weeks for excess rain.

Likely causes

Fungal Leaf Spot
Most likely
How to tell: You will see dark, circular or irregular spots appearing on the leaves during wet seasons. These spots may eventually merge and cause the leaf to turn yellow and drop prematurely.
What to do: Remove and dispose of all fallen leaves around the base of the tree to prevent spores from overwintering. Prune away heavily infected branches to improve airflow through the canopy. Avoid overhead watering to keep the foliage dry.
Poor Air Circulation
Possible
How to tell: The center of your magnolia is very dense, and the leaves remain damp long after rain. This creates the perfect environment for fungal spores to thrive.
What to do: Thin out the inner branches during the dormant season to allow light and air to reach the center of the plant. Ensure the tree is not crowded by other shrubs or structures.

Leaf spots on other plants

Find out what's wrong with your star magnolia

The list above covers the usual causes. Pocket Botanist looks at a photo of your actual plant and tells you the likely cause, how serious it is, and what to try first. Identification and a health check are free.

When to worry

It is normal to see a few spots after a very wet spring, but you should worry if the entire tree is defoliating. If the tree loses more than half its leaves, consult a local arborist.

Stopping it coming back

Keep the area around the base of your tree clean of debris and ensure it has enough space to breathe.

Star magnolia: spots? Check yours with a photo

Every plant is a little different. Take a photo of your star magnolia and Pocket Botanist tells you which cause is most likely, how serious it is, and what to try first. A few checks a day are free. Save the plant and you get care reminders timed for it.

Get the app · Or check it from a photo now, free

Questions people ask

Should I spray my tree with fungicide?: Usually, good sanitation and pruning are enough. Fungicides are rarely needed unless the infection is severe and recurring every year.
Will these spots kill my magnolia?: Leaf spot is rarely fatal, but it can weaken the tree if it happens every season. Focus on improving airflow to help the tree recover.

Guides to these causes

Leaf Spot

Why are there dark spots on my Star magnolia leaves?