Anyone using this as Insecticide?

halved garlic cloves and onion skins mixed in a blender with 2 cups water. Set the solution on a shelf overnight, then strain it and add it to 1 1/2 gallons of water to use as an insecticide.

Also, what are some other alternatives that you can spray on the leaves that would stay on them for awhile since I cannot visit often?

Thanks

no one at all?