Anthracnose

Colletotrichum species

Fungalalso: Anthracnose fruit rot, Ripe rot

A fungal disease best known for rotting ripe and overripe fruit with sunken, dark, circular lesions, though it also spots leaves and stems on many crops. On tomatoes it is the classic ripe rot, and it also strikes peppers, beans, cucurbits, and brambles. Warm, wet weather and fruit left to over-ripen on the plant make it worse.

🔎 How to spot it

On tomato and pepper fruit, look for small, round, sunken, water-soaked spots that enlarge into dark, depressed lesions up to half an inch across, often in concentric rings, mostly on ripe fruit. With age the centers turn tan and show tiny dark specks, and in wet weather they ooze masses of salmon-pink spores. On beans and other crops it makes dark sunken spots on pods, stems, and leaves.

🥀 Damage it causes

Anthracnose rots fruit on the plant and continues after harvest, so fruit can collapse in storage. It can ruin a large share of a tomato or pepper crop in a wet season, and on beans it scars pods and can spread through the seed. Leaf and stem lesions weaken the plant.

🔬 What causes it

Anthracnose is caused by Colletotrichum fungi, which overwinter in soil and infected debris and on seed. Spores are splashed up onto fruit and foliage by rain and overhead watering and can infect green fruit silently, staying dormant until the fruit ripens. The disease is favored by warm, wet, humid weather and by fruit that sits too long on the plant.

🛡️ Prevent it

Rotate crops on a two to three year cycle and start with clean, certified seed. Mulch to block soil splash, water at the base, and stake or trellis plants and keep fruit off the ground. Space for airflow, and pick fruit promptly as it ripens rather than letting it over-ripen on the plant. Clean up and destroy debris at season end.

🧯 If it is already here

Remove and destroy infected fruit and debris as soon as you see them, and harvest ripe fruit quickly to limit losses. Keep foliage and fruit as dry as possible. On valued crops, preventive applications of an approved copper-based organic fungicide, started before fruit ripens and repeated per the label, can reduce infection. Do not save seed from infected plants.

💡 Good to know

A useful clue is that anthracnose targets ripe and overripe fruit, so promptly picking fruit as it colors up is one of the best controls. The salmon-pink spore masses that ooze from the lesions in wet weather are a giveaway. Because it can ride on seed and live in debris, clean seed and good cleanup both pay off.

🌱 Plants it affects

714 plants in the library can be affected by this problem

Acorn Squash

Adirondack Blue Potato

Aji Amarillo Pepper 🍓Albion Strawberry

Alice du Pont Mandevilla 🥔All Blue Potato

American Beauty Dragon Fruit

American Beech

American Persimmon

Amethyst Falls Wisteria

Annabelle Smooth Hydrangea

Arizona Sun Blanket Flower

Atlantic Giant Pumpkin 🥕Atomic Red Carrot

Aucuba

August Beauty Gardenia

Aunt Molly's Ground Cherry

Barbara Karst Bougainvillea

Beauregard Sweet Potato

Becky Shasta Daisy

Bee Balm 🍅Beefmaster Tomato

Benarys Giant Zinnia

Bengal Tiger Canna

Better Boy Tomato 🥬Bibb Lettuce 🍅Big Beef Tomato

Black Beauty Eggplant

Black Beauty Zucchini

Black Beluga Lentil

Black Cherry Tomato

Black Crowberry

Black Currant 🍉Black Diamond Watermelon

Black Kabouli Chickpea

Black Krim Tomato

Black Raspberry

Black Sapote 🥬Black Seeded Simpson Lettuce 🥕Black Spanish Radish

Black Tartarian Cherry

Black Walnut

Black-Eyed Pea

Black-eyed Susan Vine

Blood Orange

Bloomsdale Spinach

Blue Bird Delphinium

Blue Bird Rose of Sharon

For educational and informational purposes only. Disease management advice is general guidance drawn from university cooperative extension sources; always identify a problem positively and read and follow the label on any product before use, especially around food crops, children, and pets.