Strawberry Leaf Scorch
Diplocarpon earlianum
A common fungal disease of strawberries that covers the leaves in dark purple spots and, in a heavy case, gives the whole leaf a dried, scorched, burnt look. It weakens the planting and cuts berry yield and quality, and it overwinters on old strawberry leaves, so end-of-season cleanup is key.
🔎 How to spot it
Look for many small, dark purple to reddish spots scattered over the upper leaf surface, which unlike leaf spot do not develop pale centers. As spots multiply, the leaf tissue between them reddens or purples and the leaf edges dry and curl, giving the leaf a scorched, burnt appearance. Infected fruit stalks and runners can also be marked.
🥀 Damage it causes
Heavy scorch kills leaf tissue and whole leaves, weakening the plants and reducing the number and quality of berries. Badly affected plantings lose vigor over time, and the disease can spot fruit stalks and runners, further sapping the bed.
🔬 What causes it
Strawberry leaf scorch is caused by the fungus Diplocarpon earlianum, which overwinters on infected, fallen, and old strawberry leaves. In spring and through the season its spores are splashed by rain and overhead watering onto new leaves, infecting them when they stay wet. Warm, humid weather and prolonged leaf wetness favor it.
🛡️ Prevent it
Plant on a well-drained site with full sun and good air movement, space plants for fast drying, and use drip rather than overhead watering, watering in the morning so leaves dry. Remove and destroy old, infected leaves and all plant debris at the end of the season, and renovate June-bearing beds by mowing and clearing old foliage after harvest. Use clean, resistant plants.
🧯 If it is already here
Clean up and destroy infected leaves and debris, and renovate beds after harvest to remove the source. Where scorch is severe year after year, protectant fungicides applied beginning at bloom and repeated in wet weather can help, but only alongside the cultural steps; follow the label. Keeping the foliage dry and the bed open does much of the work.
💡 Good to know
Leaf scorch is told from common strawberry leaf spot by its spots, which stay solid dark purple without the gray-tan centers that leaf spot develops, and by the overall scorched look of a bad case. Because it overwinters on old leaves, the post-harvest renovation of June-bearing beds, mowing and clearing the foliage, is a powerful control.
🌱 Plants it affects
7 plants in the library can be affected by this problem
For educational and informational purposes only. Disease management advice is general guidance drawn from university cooperative extension sources; always identify a problem positively and read and follow the label on any product before use, especially around food crops, children, and pets.