Question From: Jacksonville, Florida, United States
Q: Hello, I have a problem with my zinnias. As shown in these pictures, there are brown spots and dried leaves on them. Will I have to cut all of the flowers? Thank you.
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Sadly, your zinnias have what looks like a couple of diseases (listed below) and should be removed from the garden, roots and all and disposed of in the trash. Do not plant zinnias in that space for three years/ Blight starts as reddish brown spots with graying centers. Dark brown cankers form on the stems and flowers are spotted or completely blighted. The disease is also called alternaria leaf spot. Powdery mildew is found on zinnia, particularly late in the season. The disease causes a white to grayish powdery growth on the leaves. Bacterial leaf spot causes reddish brown, angular spots on the leaves and can cause plants to die out by mid-August. These diseases need to be treated early and followed up with weekly applications of fungicides.