Black spots on leaves

Here is an easy and effective way to cure the black spots on leaves of your roses, flowers, and other plant leaves.
Make a solution of 1 part milk to 2 parts water. Pour this solution into a spray bottle. Spray on rose leaves or other leaves.
The trick? The lactoferrin in milk, which is a subfraction of whey protein, works great as a defungicide, inhibiting a wide range of fungus, bacteria and yeast.