🍄Fungal diseasesModerate
Cercospora Leaf Spot
Risk near you, next 48h
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When it strikes
Temperature
20–32°C
Humidity
≥85%
Leaf wetness
Required
Season
Summer
About
Cercospora leaf spot affects beets, chard, peppers, carrots and many crops in warm humid weather, causing rapid defoliation that reduces root and fruit size.
Symptoms
Numerous small circular spots with tan-grey centres and distinct reddish-purple borders; spots merge and leaves brown and die in heavy infections.
Organic Treatment
Remove infected leaves, mulch, improve airflow, and spray copper in warm wet weather.
Chemical Treatment
Chlorothalonil, azoxystrobin, or difenoconazole on a 10–14 day schedule during humid periods.
Prevention
Rotate crops, use clean seed, widen spacing, and avoid overhead watering late in the day.