Description
A fungus that appear most commonly on the leaves of cucumbers and squash. Appear like a light powder white on the leaves, that appear in a spot formation. These white spots can spread quickly if left unchecked. Powdery mildew appear when humidity and temperatures are high.
Effects
Powdery mildew often looks worse than it is. Often it will not kill the plant, but if it is not controlled it can spread to other crops and cause your plants to start to loose leaves or make the leaves curl.
Control
The best control is to remove affected leaves right away. You can also prevent powdery mildew, or prevent it from spreading by spraying leaves every few days with a Baking soda solution {1 tsp baking soda to 1 litre of water with a few drops of dish soap (Sunlight is best) in a spray bottle}. This changes the pH of the surface of the leaves making it impossible for the powdery mildew to establish itself.