Why do my plants have white spots on the leaves and how can I treat this issue effectively?

White spots on plant leaves are often caused by fungal diseases like powdery mildew or pests like spider mites. To effectively treat this issue, you can try removing the affected leaves, improving air circulation around the plants, and using organic fungicides or insecticidal soaps. It's also important to water the plants at the base to avoid wetting the leaves, as moisture can promote the growth of fungi.