Hydrangea: Failure to bloom Categories: Hydrangea Hydrangea Diseases Ornamentals Shrubs Last review date: 2025-06-28 11:40 Last edit date: Biology Improper pruning is the most common reason hydrangeas fail to bloom. Both bigleaf (Hydrangea macrophylla) and oakleaf (H. quercifolia) hydrangeas produce their flowers on the previous year’s growth. If these stems are removed, new growth may […]
Hydrangea: Fungal leaf spots Categories: Hydrangea Hydrangea Diseases Ornamentals Shrubs Last review date: 2026-06-14 02:47 Last edit date: Mycosphaerella leaf spot, www.forestryimages.org Photo by: B.J. Jacobsen, NCSU Biology Several fungal diseases cause spotting of leaves on hydrangeas. Symptoms may include brown, black, or gray spots or angular blotches. These may be surrounded by a reddish […]
Hydrangea: Hail damage Categories: Hydrangea Hydrangea Diseases Ornamentals Shrubs Last review date: 2026-06-14 02:51 Last edit date: Hail damage to hydrangea leaf Photo by: J. Glass Biology Damage to plants depends on size of the hailstones and intensity of the storm. Minor damage may not show immediately but may appear days or weeks later as […]
Hydrangea: Herbicide damage Categories: Hydrangea Hydrangea Diseases Ornamentals Shrubs Last review date: 2026-06-14 03:07 Last edit date: drought damage to H. macrophylla Photo by: R. Maleike Biology Symptoms of herbicide damage may be confused with damage from insects, disease, or cultural problems. Specific injury symptoms vary depending on degree of exposure, product used, and plant […]
Hydrangea: Leaf scorch Categories: Hydrangea Hydrangea Diseases Ornamentals Shrubs Last review date: 2026-06-14 03:27 Last edit date: Leaf scorch on hydrangea Photo by: J. Glass Biology Leaf scorch on hydrangea is a common physiological problem. Typical symptoms include yellowing leaves, or irregular dry, brown blotches. Leaf tips and margins may turn brown, as well. Severely […]
Hydrangea: Marginal leaf necrosis Categories: Hydrangea Hydrangea Diseases Ornamentals Shrubs Last review date: 2026-06-14 03:33 Last edit date: drought damage to H. macrophylla Photo by: R. Maleike Biology Browning and dieback of leaf margins and tips can be a symptom of several problems that restrict water flow to the leaves. Drought, excess heat, excess sunlight, […]
Hydrangea: Powdery mildew Categories: Hydrangea Hydrangea Diseases Ornamentals Shrubs Last review date: 2026-06-14 03:49 Last edit date: Powdery mildew on hydrangea Photo by: Dept. of Plant Pathology, NCSU Biology Powdery mildew is a fungal disease affecting leaves, young shoots, and flowers. White to grayish, powdery fungal growth develops on the top of the leaf and […]