Have white spots on leaves of my plants. Looks like they have a disease.
Oh dear, white spots on plants are also known as POWDERY MILDEW. This is a fungal disease. To get rid of it, spray on the plants to eliminate and/or prevent mildew growth. Add ½ teaspoon baking soda per quart of water. Spray. Oil sprays consisting of neem oil, sesame oil or fish oil work on powdery mildew as it does on many fungal diseases.