Hello Richard,

It is likely that the curling leaves is a response to environmental conditions. Leaf curling is a common response to heat or drought stress. Magnolias have shallow root systems which makes them sensitive to hot and dry conditions.

You could inspect the tree for insect pests, such as aphids or magnolia scale that suck nutrients from the tree. Magnolia scale is easily identifiable: https://www.canr.msu.edu/news/check_magnolias_for_magnolia_scale_now

To scout for aphids, shake a branch over a piece of white paper and the insects will fall out. When these sucking insects are present they excrete a honeydew which coats the branches and sooty mold appears, turning the branches black.

The best treatment is to ensure that the tree receives adequate moisture, one inch of water a week and by applying 2 inches mulch over the root zone (but not up against the trunk) to keep the area moist.

MSU Extension’s Plant and Pest Diagnostic Lab can provide a diagnosis. To learn how to submit a sample, go to: https://www.canr.msu.edu/pestid/

A certified arborist can also assess your tree. To find an arborist in your area, go to: www.treesaregood.org, the website of the International Society of Arboriculture.

Thank you for contacting Ask Extension.