powdery mildew and bee balm
I have bee balm plants that have powdery mildew. 3 questions: is it caused by wet or dry conditions? Is a spray of water and milk really an effective preventative? Once it is on the plant, how can I get rid of it (i.e. commercial spray or other recommendation)?
Powdery mildew loves moist conditions, though even plants that are somewhat dry can be affected. A weekly spray of milk at a concentration of 1 part milk to 9 parts water may significantly reduce the severity of powdery mildew infections. Neem oil is also effective in treating powdery mildew. For more information, these articles will help: https://www.gardeningknowhow.com/plant-problems/disease/get-the-cure-for-powdery-mildew.htm