Phytophthora cinnamomi

Plant Damange:

Root rot and root crown rot.

Multiple Hosts:

  • Heath & Heather (Erica)
  • Hemlock (Tsuga)
  • Juniper (Juniperus)
  • Mountain laurel (Kalmia)
  • Rhododendron (Rhododendron)
  • many others


One of the most common Phytophthora diseases of nursery crops grown in the field or in containers. It is favored by waterlogged soils and warm temperatures.


This pathogen infects only roots during prolonged periods of soil or media saturation. The disease progresses throughout the root system and can move into the root crown. A main stem canker can develop just above the root crown area.


This pathogen survives as spores in the soil or container media, or in infected host roots.