Dews and humidity in the past few days

We have not received precipitation since the 21st, but every night since then has been humid.  Dews that formed 3-4 AM stayed until 9-10 AM in some days.  Once again, these conditions favors downy mildew spore development. 

If your vines are covered with a previous application, you do not need to worry about it, but if not (say, the last application was more than 10 days ago, or you had more than 1.5-2 inches of rain since the last application), then you may want to consider a protective application before next thunderstorm hits, which may happen in the next few days.  We are almost through with the critical period, though!

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