Downy mildew in onions: IPM guide

Downy mildew is a widespread fungus-like disease in onions and other Alliums. Infections rarely kill onion plants but will cause early leaf dieback and infect the neck of the bulb, making greens unmarketable and reducing bulb size and storage quality.

This guide contains integrated pest management (IPM) information tailored for small-scale production, but the guidelines can be applied to all operation sizes. It includes:

  • Identification and lifecycle details including photographs of pest phases
  • Information about how and when to monitor
  • Options for biological, cultural, physical and chemical control

This resource was developed as part of a 12-guide series for small-scale vegetable and berry farmers in the Fraser Valley and Lillooet-Pemberton areas. Growers in other regions of BC may also find the information applicable to their local conditions. A webinar shares more information about the project.


IPM Guide - Downy Mildew in Onions - 2021

4 MB, pdf