Spots on foliage are usually caused by watering late in the day or on cloudy days, plus not enough air circulation. Here’s a few things you can change that will help you grow a healthier plant – water at the base rather than overhead, water in the morning, and plant in a spot with good air movement. Neem oil or a fungicide will help clean up the black spot fungus and keep it from spreading to other plants. Making the changes in watering will also help prevent it from coming back.
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