Powdery mildew is a fungous unwellness that affects a large vary of plants. Powdery mildew diseases square measure caused by many alternative species of fungi within the order Erysiphales, with Podosphaera xanthii (a.k.a. Sphaerotheca fuliginea) being the foremost ordinarily rumored cause.
There square measure many alternative species of the fungous unwellness mildew, and every species attacks a spread of various plants. not like several different fungous diseases, mildew thrives in heat, dry climates, although it will need fairly high ratio (i.e., wetness round the plant) to unfold. In cooler, rainy areas, it doesn't unfold likewise. That being aforesaid, it's capable of infecting your plants beneath a large selection of conditions.
Although mildew affects an excellent variety of plants, the various mildew fungi square measure host specific, which means every of the mildew fungi infects solely specific plants. Thus, the mildew on your lilacs won't unfold to your grapes or your roses. However, all powdery mildews favor constant weather.