powdery mildew

noun

1
: an ascomycetous fungus (family Erysiphaceae) producing abundant powdery conidia on the host
2
: a plant disease caused by a powdery mildew

Examples of powdery mildew in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Avoid problems with powdery mildew by properly spacing plants to ensure good air circulation. Kim Toscano, Southern Living, 3 July 2025 Dahlias are susceptible to powdery mildew, so be sure to allow proper airflow around each plant to keep them healthy. Mary Marlowe Leverette, Southern Living, 9 July 2025 Wet plant parts are most prone to powdery mildew growth. Leanne Potts, Better Homes & Gardens, 8 July 2025 The only exceptions are: – When plants have powdery mildew, selectively remove branches (not just leaves) to improve air circulation. – When branches/leaves touch mulch or soil. Nan Sterman, San Diego Union-Tribune, 6 July 2025 See All Example Sentences for powdery mildew

Word History

First Known Use

1889, in the meaning defined at sense 1

Time Traveler
The first known use of powdery mildew was in 1889

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Cite this Entry

“Powdery mildew.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/powdery%20mildew. Accessed 25 Jul. 2025.

Kids Definition

powdery mildew

noun
: a fungus that is a parasite and produces a large number of powdery spores on the host
also : a plant disease caused by such a fungus

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