|Mike's Gardening Tips
"The Cornell Formula"--a natural plant fungicide
Developed at Cornell University, this baking-soda based remedy is a great spray-on plant disease preventative and fighter. It's as good as any chemical fungicide you can buy--the only thing that's stronger is Fermented Compost Tea (details on this SUPER disease fighter can be found elsewhere on this site).
To use The Cornell Formula, get a sprayer (anything from a hand-held one-gallon job to those really cool big-boy backpack styles), and mix this up right inside the container part of the sprayer...
Note: the "oil" to be used is ideally horticultural oil (also known to many folks generically as 'dormant oil', although that term, in truth, refers to a specific type of hort oil.) For this recipe you can use any grade of the stuff all the way from true dormant oil (very heavy petroleum product) to the new lighter-weight "summer oils" (vegetable oil based). Horticultural oil is available at all nurseries and garden centers and is an essential tool for tree owners (especially of fruit trees) who use it to smother over-wintering tree pests. If you intend to use this spray a lot (like to protect disease-prone roses), buy some real hort oil--I'd recommend one of the lighter summer oils.
In a pinch you can use regular vegetable oil from the kitchen, but hort oil will work better. And no, 'duct-tape gardeners', you can't be a cowboy and use motor oil or WD-40 or any other such foolish thing. I will find out if you do and make you sorry.
Don't spray in direct sun in the heat of the day. Early morning is good; late evening is fine too.
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