Marginal leaf necrosis

Leaf edges brown and die back progressively, often from water stress during dry periods or low potassium availability in the soil. Maintain consistent watering throughout the entire growing season and check soil fertility with a professional soil test. Ensure good drainage to prevent root stress and anaerobic conditions. Potassium fertilizer applications may help if deficiency is confirmed by testing.

Good sanitation is your most effective tool against marginal leaf necrosis. Remove and dispose of infected plant material, clean up fallen debris, and sterilize your pruning tools between plants. Reduce leaf wetness by watering at soil level and spacing plants for adequate air movement. These practices reduce the pathogen load in your garden over successive seasons.