Powdery Mildew prevention

Asked May 7, 2020, 11:58 PM EDT

Hi, I had powdery mildew last year in my vegetable garden. After reading many articles I realize that I created a perfect environment for it to grow! Darn it! This year I would like to help my soil have a head start. Is there anything I can add to give it a boost before planting? Also, are there certain vegetables besides the obvious squash, melons, cucumbers and tomatoes that I should avoid?
Thanks so much, Sabrina

Garfield County Colorado

1 Response

Thank you for using the Ask an Expert Service!

Cultural Practices are the best way to prevent Powdery Mildew in the future, here is our list of suggestions:

  • Avoid late-summer applications of nitrogen fertilizer to limit the production of succulent tissue, which is more susceptible to infection.
  • Avoid overhead watering to help reduce the relative humidity.
  • Remove and destroy all infected plant parts (leaves, etc.). For infected vegetables and other annuals, remove as much of the plant and its debris in the fall as possible. This decreases the ability of the fungus to survive the winter. Do not compost infected plant debris. Temperatures often are not hot enough to kill the fungus.
  • Selectively prune overcrowded plant material to help increase air circulation. This helps reduce relative humidity and infection.
For more information, please check out our Fact Sheet: https://extension.colostate.edu/topic-areas/yard-garden/powdery-mildews-2-902/
And our Article:
https://planttalk.colostate.edu/topics/insects-diseases/1415-powdery-mildew/

Thanks,