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

Humid weather and overly dense plants create the ideal conditions for powdery mildew spores to settle on leaves and spread. — Nan Sterman, San Diego Union-Tribune, 1 Aug. 2026

If your peonies were suffering from powdery mildew or another disease, throw the cuttings in your trash or burn barrel to keep problems from spreading. — Lauren Landers, The Spruce, 31 July 2026

Watering in the evening increases the chances of fungal diseases like powdery mildew and blight developing on your plants if moisture remains on the leaves overnight. — Karen Brewer Grossman, Southern Living, 22 July 2026

Baking soda can help prevent powdery mildew, kill weeds, repel slugs, and clean produce, but must be used sparingly. — Lauren Landers, Better Homes & Gardens, 21 July 2026

Word History

First Known Use

1889, in the meaning defined at sense 1

Rhymes for powdery mildew

• accrue
• ado
• ainu
• aircrew
• airscrew
• anew
• askew
• baboo
• babu
• bamboo
• beaucoup
• bijou

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