Disease Directory

    Anthracnose

    Colletotrichum spp., Discula spp., Elsinoe spp., Glomerella spp.

    Fungus
    Leaves
    Stems
    Fruit
    Flowers

    Overview

    Anthracnose covers several Colletotrichum and related fungi that leave dark, sunken lesions on leaves, stems, flowers, and fruit. Wet weather brings salmon-pink spore masses on lesions, spreading disease through splash and tools. Beans, cucurbits, peppers, tomatoes, and many woody ornamentals are common hosts in home gardens. Anthracnose spreads mainly by spores on wind, splash, tools, and crop debris. Humid, crowded plantings and overhead watering favor outbreaks in home gardens and food forests. Causal agent: Colletotrichum spp., Discula spp., Elsinoe spp., Glomerella spp.. In regenerative gardens, prioritize sanitation, airflow, and unbroken soil cover over calendar spraying, and intervene early when symptoms appear.

    Symptoms

    Dark, sunken, water-soaked lesions on leaves, stems, and fruit; centers may turn tan with dark borders. In humid spells, salmon-pink spore masses appear. Leaves can distort and drop; fruit develops sunken rot that ruins harvest quality. Compare several plants and note whether symptoms spread after rain, insect feeding, or wet foliage. Photograph undersides of leaves and cut stems when wilt is present to refine the diagnosis. Rule out simple drought, fertilizer burn, and herbicide drift before assuming a pathogen - abiotic injury often mimics disease.

    Environmental Conditions

    Humid

    Prevention

    Plant resistant varieties when offered. Prefer drip irrigation over overhead. Rotate out of susceptible crops and remove debris. Apply preventive copper only where pressure is high and labels allow. Buy certified clean transplants. Mulch to reduce splash, clear season-end debris, and avoid working plants when wet. Design beds for airflow and diverse plantings that support beneficial insects without creating permanent humid pockets around susceptible crops.

    Management

    Prune or pick off infected tissue and destroy it. Avoid handling plants when wet. Improve drainage and spacing. Copper or labeled organic fungicides at first signs slow spread; hot-water seed treatment helps some vegetable crops. Do not save seed from infected fruit. Prefer drip irrigation, morning watering, and open spacing so leaves dry quickly. Disinfect pruners between cuts on woody plants. Use copper, sulfur, or biological products only as labeled protectants when pressure is high - they rarely reverse advanced infections alone. Destroy (do not casually compost) highly infectious debris.