What is the difference, in appearance, between downy mildew and powdery mildew?
Downy and powdery mildew are very similar, causing a fuzzy white or purple covering on leaves, flowers and stems. Downy mildew tends to grow on leaf undersides while powdery mildew appears on upper surfaces of leaves and on flowers. Sometimes powdery mildew causes red or purple discoloration in affected leaves. Upper surfaces of leaves with downy mildew become pale, show angular yellow spots and sometimes wilt.
