Common leaf spot is an important and wide spread disease of strawberries. Common leaf spot is serious in very wet years.
Common leaf spot [Mycosphaerella fragariae]
Common leaf spot - image 1
The fungus overwinters on infected plant parts. Infection starts in the spring. Spreading is by conidia, which are transported to surrounding foliage by rain drops. The fungus invades the plant via the stoma and causes white spots with brown edge zones on the leaves (Picture 1). Wet weather conditions favor the spread of this fungus.
As a preventive measure, older leaves should be removed when new growth starts. Grow strawberries on light well draining soil in an area with good wind circulation. Select resistant varieties. Use a fungicide spray program.