There are some interesting, simple remedies for powdery mildew ( things
like diluted milk and baking soda solution) but I've never heard of this
one.
Taylor is right that use of conventional chicken feed in this way on
certified organic ground would result in loss of certification on the field
where it was used. Reason: conventional chicken feed will contain, among other
things, genetically modified corn and soy.
ATTRA has some documents on disease control in various plants that
sometimes include the simple home remedies.
Pat Whetham
Organic inspector