Precipitated primarily by::: TEMPERATURES.
The recent outbreak of powdery mildew was reported by cookie monster after cool moist nights 60-72F (ideal 69.8F for max. fungus pwd mildew growth) reaching far south florida. Also day temperatures were not reaching 86F probably. Can not verify all areas.
It's good to know similar situation occurs in COOL moist environments usually dark at night. (Cooler in Orlando & Loxahatachee etc. than Delray/miami/etc. normally at night)
Grass looks as though it is sprinkled with flour. Kentucky bluegrass and shade areas are the most susceptible. Grass will wither and die. It is FAVORED BY TEMPERATURES of 60-72 F
Water only in the morning; reduce shade by pruning, aerate and check drainage in the area.
Note that whereas the fungus can multiply rapidly when temperatures are in the mid-60s to mid-80s, it is inactive while temperatures remain above 90†F. In fact, some spores and colonies are killed after relatively short exposures above 95†F
Most powdery mildews have an optimum temperature of 21°C (Celio & Hausbeck, 1998). The germination of spores is less efficient at higher temperatures. Also the growth of hyphal threads will be curbed at higher temperatures. There is no infection if the temperature is above 30 ,(C. Research has found that the maximum temperature is 30 °C for appresoriumformation, while the colonies die at a temperature of 32°C (Quinn & Powell, 1982). Mildew will not die at lower temperatures, but its growth will decrease.
1 =favored temp.60-72F
#2 Mid 60s to mid 80s F and slow at 90F and some killed at 95F
#3 21C = 69.8F = great powdery mildew temperature for growth
#3 No infection if above 30C = 86F = Lucky Miami a lot of the time for less fungus growth.
...Just thought I would open a few eyes...
I might as well add a link to the highly paid professionals opinion... aka pot growers...https://www.420magazine.com/forums/frequently-asked-questions/102994-powdery-mildew.html