Camellia: Flower and petal blight

categories: Camellia Camellia Diseases Ornamentals Shrubs

revision date: 2022-11-30 12:00

Camellia flower blight: healthy vs. diseased blooms.
Camellia flower blight: healthy vs. diseased blooms
Photo by: OSU slide library

Biology

Flower and petal blight is a fungal disease of camellia flowers. Leaves, stems, and roots are not attacked. Symptoms begin with development of brown spots on the petals. These spots quickly enlarge until the entire flower is brown and dry or leathery and drops from the plant. Dark brown veins in lighter brown petals are a characteristic symptom. Olive-brown or black fungus bodies, up to an inch in diameter, can develop in the bases of infected flowers. These fungal structures persist in the soil, causing reinfection. This disease may be confused with injury caused by weather, which is usually only found on the outer margin of flowers. Disease development is favored by cool, wet conditions. All species and varieties of camellia appear equally susceptible to this blight.

Management Options

Use Integrated Pest Management (IPM) for successful plant problem management.

Non-chemical Management

Select non-chemical management options as your first choice!

  • Plant only disease-free materials. To reduce chances of planting infected materials, it is best to plant bare-root plants with no color showing in the buds.
  • Remove and destroy diseased flowers to reduce chances of reinfection.
  • Remove and destroy (do not compost) all plant debris from beneath camellias.
  • Remove 3-4 inches of soil beneath diseased shrubs and replace with clean soil to help reduce reinfection.

Chemical Management

IMPORTANT: Visit Home and Garden Fact Sheets for more information on using pesticides.

  • Apply to foliage to protect blooms as flower buds begin to swell.

Approved Pesticides

Listed below are examples of pesticides that are legal in Washington. Always read and follow all label directions.