Why Does My Magnolia Bush Have Yellow Leaves?

Identification

• Magnolia plants are susceptible to oleander leaf scorch caused by Xylella fastidiosa. Pests like the sharpshooters are the primary vectors of the bacterium. The insects feed on the water conducting tissues of plants and transmit the disease.

Damage

• Disease-causing bacteria are most active during late spring and summer. Initial symptoms include yellowing and drooping foliage in certain areas of the plant. Foliage margins gradually turn dark yellow to brown and there is leaf drop. As disease progresses, the bacteria spreads throughout the plant and branches start to die. The entire plant is eventually killed.

Management

• Oleander leaf scorch is a lethal disease with no known cure. Planting resistant varieties reduces chances of disease. Remove infected plants early to minimize risk of spreading bacteria to other plants.