Skip to content
growing.guide
Menu

Anthracnose

Anthracnose fungi cause dark, sunken lesions on beans, cucumbers, melons, tomatoes and avocados. On fruit they appear as ripening begins; spores ooze in pink masses and splash to the next plant.

Fungal diseases
A fruit with a sunken, dark anthracnose lesion
A fruit with a sunken, dark anthracnose lesion

What it looks like

Sunken is the key word.

  • Round, dark, sunken patches on ripening fruit.
    Sunken fruit spots Round, dark, sunken patches on ripening fruit.
  • Salmon-pink masses in the centre in wet weather.
    Pink spores Salmon-pink masses in the centre in wet weather.
  • Angular brown spots on cucurbit leaves that drop out.
    Leaf spots Angular brown spots on cucurbit leaves that drop out.
  • Dark sunken lesions with red-brown rims on beans.
    Pod lesions Dark sunken lesions with red-brown rims on beans.

How to confirm it

Look closely at the lesions.

  1. Sunken, not raised

    Lesions dip into the fruit.

  2. Pink ooze

    Pink spore masses in humid weather.

  3. Wet weather

    Follows warm, wet spells.

What to do

Remove and prevent spread.

  1. Pick affected fruit

    Remove and bin spotted fruit and pods.

  2. Stay out when wet

    Do not work among wet plants.

  3. Mulch

    Keep fruit off the soil.

  4. Harvest promptly

    Pick fruit as soon as ripe.

Prevent it next time

  • Use clean, certified seed for beans.
  • Rotate crops for two years.
  • Water at the base.

What not to do

Do not save seed from infected bean pods.

In the growing guides

Where the guides mention it, with plant-specific advice.

Sources

  1. Anthracnose on vegetables, University of Maryland Extension