Milk? wow I never thought of that one. I think in this case the plant was simply under stress and susceptible to anything. There is plenty of air circulation. It is growing on a trellis about 20" from a wall just for that purpose. I believe someone dropped the ball and forgot to turn on the automatic irrigation and first it got too dry then too wet when the water was turned on.
This is a children's garden at a library so milk would be the perfect solution, safe for kids and critters. How do you use it? Whole milk or skim? what dilution?
I can't wait to pass this info on.