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You can recognize leaf spot disease by the characteristic white, reddish-brown edged spots on the foliage of strawberry plants. Round, reddish-brown, purple to crimson spots with gray to whitish centers form primarily on the upper surface of the leaves. 

Symptoms are similar to red spot disease (Diplocarpon earliana), but its leaf spots lack the white center. In both cases, the older leaves are affected first. The two different fungi often occur together. 
The 1 to 5 mm spots enlarge in moist weather and merge over time. Severe infestation can lead to withering and death of the leaves. The plants are significantly weakened by the loss of assimilable leaf area. Infestation of the fruits is rarely observed.

The fungal spores that cause leaf spot disease overwinter in the form of conidia, sclerotia, and with the help of perithecia on the affected leaves. During the growing season, the fungus spreads via conidia that are spread to the healthy leaves of neighboring plants by rain splash. In particular, heavy rainfall and generally wet weather conditions therefore intensify the infestation. Stronger leaf infestation is also usually to be expected after harvest. The fungus Mycosphaerella fragariae also spreads via leaf contact of neighboring plants.

Several preventive measures can help you minimize or prevent leaf spot disease infestation;

• Different strawberry varieties have different susceptibilities. With a suitable choice of variety, you can already take good remedial action. 
• All measures that promote rapid drying of the plants are helpful as a preventive measure. 
• Straw placed under the strawberry plants keeps the plants dry and has a preventive effect. 
• A wide planting distance means that the plants do not or hardly touch each other and also dry out more quickly. 
• Additional regular weed control also helps the plant stand dry out better. 
• Excessive nitrogen applications weaken plants and promote susceptibility to the fungus. Feed your plants optimally.
• If there is an infestation, remove most of the foliage after harvest so that the new shoots are free of infestation. Mowing off the old leaves after harvest is recommended. 
• In addition, the plantings should be renewed in time.

Targeted control, especially after harvest and in acute cases, can be achieved with copper-based sprays, taking into account the current approval situation. Other fungicides can also be used, depending on the approval situation. 

When the typical spots appear, a plant protection treatment after harvest is recommended.

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