Blossom end rot is a disorder caused when developing fruit can't get enough calcium. It can cause large, dark lesions to form that can cover as much as 1/2 of the fruit. Because it is not a disease, fungicides and other disease control products are ineff
Black spot can be found on numerous plants - including roses, flowers, fruits, and leaves. It is especially problematic when the weather is hot and humid.
Late Blight disease is an aggressive fungus-like pathogen that thrives in cool, damp weather. It attacks tomatoes and potatoes, among other plants. Young lesions are small and appear as dark, water-soaked spots.
Powdery mildew is a fungal disease that thrives in both wet and dry conditions. It grows on the outside of leaves, forming a white or grayish powder of spores and fungal strands.
Rust diseases produce raised pustules that rupture to release powdery, orange to red-colored spores on the underside of affected leaves. Light yellow spots can be seen on the upper leaf surface.