Powdery Mildew on the Squash

Yesterday, I noticed that my squash had some white, powdery looking spots on it’s leaves.

The plant itself looked okay other than the spots.

I noticed the other day that while some of the fruit were okay, a couple of the fruits just coming on appeared to have started to rot where the flower typically falls off.

 So, obviously, I had to do something, the first thing I did was find out what I had.  My twitter friends told me I likely had Powdery Mildew.  The first thing I did was to cut off the healthy fruit.  Though I would normally leave it to grow a bit more, I preferred to cut it off than to leave it and have it rot.

The next thing I did was to cut off all of the dead leaves, the dead flowers, rotted fruit/flowers, dying stems, and the leaves that were very badly covered in mildew.  I used sharp pruners and put the damaged leaves on my scrap pile.

Now, I had several options.  There were lots of different suggestions to try to prevent powdery mildew (not a lot of treatment options, mostly preventatives).  The one I decided to try was a combination of baking soda, water, and a touch of dish soap.  
I took a quart sized spray bottle I got from the dollar store and added a drop of liquid dish detergent (the off brand of Dawn, the blue kind is what I used, then added 1 1/2 teaspoons of baking soda.  I mixed this well, then squirted on all sides of the leaves, including the stems.  I more or less drenched the entire plant to the point of run-off.
I did this in the evening, after the sun had gone down, to be sure that the sun didn’t scorch the plant with the soap.  By mid-morning the next day, the leaves that did have small powdery mildew spots on them were gone, but a small yellow spot was left.  The whole plant looked happier.

I have hopes that some of the remaining blooms will be able to make it to harvest still, currently, they have teeny-tiny squash coming on – with no mildew!

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