HARRISBURG, Pa. — This spring, Pennsylvania was among 28 states where retailers received rhododendrons that may have been exposed to a plant pathogen called Phytophthora ramorum. The pathogen causes infectious disease in popular Pennsylvania plants and shrubs including rhododendron, mountain laurel, lilac, viburnum and pieris.
Anyone who has recently purchased a rhododendron should monitor the plant for signs of disease, including leaf spots and shoot dieback. Other rhododendron problems may mimic the disease, but a lab test can confirm.
If you suspect your plant may have the disease, contact your county’s Penn State Extension office or the Department of Agriculture regional office for instructions on how to send in a sample for testing.
For more information about protecting Pennsylvania’s plants and landscapes, visit agriculture.pa.gov.