Dark Spot Plant Disease, also known as Diplocarpon rosae is a sort of plant fungus. The Black Spot disease moves from the lower leaves of a plant upward causing leaf drop and dark spots with circular punctured edges. Plants severely infected with Black Spot Disease do not appear the circular pattern since the spots combine to make an expansive dark mass. The leading treatment for Dark Spot Disease is to expel the contaminated leaves and any fallen leaves, do your best to avoid getting the plant leaves damp, and shower the plant with a Fungicide made particularly for Black Spot Disease. Diluted Neem Oil is an alternative option for treating Dark Spot Illness. Whichever item you select, shower each 7-10 days amid the hottest portion of the growing season since the fungus is most active when the temperature is between 75 to 90 degrees. Keep any plants contaminated with Dark Spot Infection quatrined from your other plants.