Lavender has few pests and diseases and is often promoted as a sustainable crop because growers do not commonly need to apply pesticides and fertilizers in its production. However, recently growers have been reporting plants with symptoms of Phytophthora root and crown rot (PRCR).
On this webpage, we aim to share information about PRCR of lavender and provide resources for managing the disease.
Phytophthora species are microscopic organisms that cause disease in plants. Many species have been identified as the primary causes of root and crown rot of their host plants. Much of our research is focused on this group of microbes.
Click here to find resources about the Best Management Practices for managing Phytophthora in ornamental plant nurseries. Most of these management practices can be applied to control or limit the effects of Phytophthora in any system.
Click on the image above to view or download a presentation (pdf) we prepared for the Washington Lavender Association Meeting in Ellensburg, WA (March 24, 2017) .
- Two Species of Phytophthora and Other Root Pathogens Isolated from Lavender Plants from 11 States in 2015. Margaret R. Williamson, Suzette R. Sharpe, and Steven N. Jeffers. Department of Plant Industry, Clemson University, Pendleton, SC, USA and Dept. of Agricultural and Environmental Sciences, Clemson University, Clemson, SC, USA.
- Root rot of lavender caused by Phytophthora nicotianae, M. Putnam, 1991. British Society for Plant Pathology.
Contact us for a copy of the research publications.
Phytophthora Root and Crown Rot
- Phytophthora root rot of lavender identified in Ontario (website)
- Root Rot of Lavender: Scouting is the Key to Prevention (article)
- Be on the Lookout for Phytophthora on Lavender (article)
- Pacific Northwest Plant Disease Management Handbook – Lavender-Root Rot (website)
- Pest Notes: Soil Solarization for Gardens & Landscapes Management, UC ANR Publication 74145 (website)
Other Diseases and Pests of Lavender
- Pests and Diseases – A summary of pests and diseases of lavender from Suffolk Lavender Farm, UK
You are welcome to contact us for more information.
If you are interested in participating in our lavender root rot research project and/or would like to subscribe to an email mailing list about this subject, fill out the form on the right.