How to Treat and Prevent Anthracnose?

HomeProblemsDiseaseHow to Treat and Prevent Anthracnose?



Anthracnose. The mere mention can send shivers down the spines of seasoned gardeners and evoke visions of disfiguring lesions, stunted growth, and withered flora. This fungal disease, a common enemy of countless plant species, casts a long shadow over verdant dreams. But fear not, green thumbs! Armed with knowledge and proactive strategies, you can effectively combat anthracnose and safeguard your garden’s precious bounty.

What is Anthracnose?

Anthracnose is a fungal disease that manifests in a variety of ways across different plants. From sunken lesions on fruits and leaves to discolored stems and wilting branches, its signature symptoms can inflict serious damage on a wide range of horticultural treasures, from roses and avocados to beans and strawberries. Left unchecked, it can wreak havoc on yields, aesthetics, and overall plant health.

The culprit behind this widespread ailment is a diverse group of fungal pathogens residing within the genus Colletotrichum. These microscopic opportunists thrive in humid environments, particularly during warm or cool wet periods. They feast on plant tissues, leaving behind telltale signs of their destructive feast.

Why Treat and Prevent Anthracnose?

Prompt action against anthracnose is crucial for several reasons. Firstly, early intervention minimizes the spread of the fungus, protecting neighboring plants from its insidious reach. Secondly, addressing the disease swiftly helps maintain plant vigor and productivity, ensuring healthy harvests and vibrant landscapes. And lastly, tackling anthracnose proactively promotes a balanced garden ecosystem, fostering a strong foundation for future growth and flourishing biodiversity.

What are Anthracnose Symptoms?

The symptoms of anthracnose vary depending on the host plant and the fungal species involved. However, some common signs include:

  • Small to large irregular brown or black spots or blotches on leaves. The spots may have yellow or red margins and may coalesce to form larger patches. The spots may also fall out leaving holes in the leaves.
  • Curling or cupping of leaves due to distortion of leaf tissues.
  • Premature leaf drop or defoliation of the plant.
  • Sunken or raised lesions on stems or branches. The lesions may girdle the stem and cause dieback or cankers.
  • Dark brown or black spots or rots on fruits or flowers. The spots may be covered with pinkish or orange spore masses in moist weather. The fruits may crack or shrivel and drop prematurely.

How Does Anthracnose Spread?

Anthracnose fungi can survive on infected plant debris or alternative hosts. They produce spores that are dispersed by wind, rain splash, insects, animals, tools, or human activities. The spores germinate and infect the plant through natural openings or wounds when there is enough moisture and a favorable temperature (usually between 15°C and 30°C). The infection cycle can repeat several times during the growing season.

How to Treat Anthracnose?

The best way to treat anthracnose is to prevent it from occurring in the first place. However, if you notice anthracnose symptoms in your plants, you need to take some steps to reduce its impact and prevent further spread.

  • Remove and destroy any infected plant parts as soon as possible. Do not compost them as the fungi may survive and infect other plants.
  • Prune out any dead or diseased branches or twigs from trees or shrubs. Disinfect your pruning tools between cuts with a 10% bleach solution or rubbing alcohol.
  • Apply fungicides to protect healthy plant tissues from infection. Choose a fungicide that is labeled for anthracnose control on your specific plant type and follow the instructions carefully. Some examples of fungicides that can be used against anthracnose are copper-based products (such as Bordeaux mixture), chlorothalonil (such as Daconil), mancozeb (such as Dithane), propiconazole (such as Banner Maxx), azoxystrobin (such as Heritage), pyraclostrobin (such as Insignia), or flutriafol (such as Impact). You may need to repeat the application every 7 to 14 days depending on the weather conditions and the severity of the disease.
  • Avoid overhead watering or irrigation that can create wet foliage and favor fungal growth. Water your plants at the base or use drip irrigation systems.
  • Improve air circulation around your plants by thinning out dense foliage or planting them at adequate spacing.

What Causes Anthracnose?

  • Environmental Conditions: Warm and humid weather provides an ideal environment for anthracnose fungi to thrive.
  • Plant Stress: Stressed plants, whether due to inadequate nutrition, drought, or other factors, are more susceptible to anthracnose.
  • Poor Drainage: Excess moisture in the soil, often resulting from poor drainage, creates conditions conducive to anthracnose.
  • Infected Plant Debris: Infected plant debris left in the vicinity can serve as a source of spores, leading to recurring infections.

How Can Anthracnose Be Prevented?

  • Select Resistant Plant Varieties: Choose plant varieties that are resistant to anthracnose, especially in areas prone to fungal diseases.
  • Proper Watering: Water plants at the base to avoid wetting the foliage, and water early in the day to allow sufficient time for leaves to dry before evening.
  • Adequate Spacing: Plant trees and shrubs with adequate spacing to promote air circulation and reduce humidity around plants.
  • Regular Inspections: Conduct regular inspections of plants to detect and address anthracnose at its early stages.
  • Mulching: Apply organic mulch around plants to regulate soil temperature and moisture levels, preventing the splash dispersal of spores.


Anthracnose, although a formidable foe, does not necessitate surrender. By equipping yourself with knowledge, adopting preventative measures, and taking swift action when required, you can shield your beloved plants from its grasp. Remember, a vigilant gardener armed with understanding and proactive strategies can create a haven where blooms flourish and fruits abound, free from the shadow of anthracnose.


How do I know if my tree has anthracnose?

Some signs that your tree may have anthracnose are brown or black spots or blotches on the leaves, curling or cupping of the leaves, premature leaf drop, dieback or cankers on the branches, and reduced growth or vigor.

What is the difference between anthracnose and leaf spot?

Anthracnose and leaf spot are both fungal diseases that cause spots on leaves. However, anthracnose spots are usually irregular in shape and have sunken centers, while leaf spot spots are usually circular and flat. Anthracnose can also affect other parts of the plant such as stems, fruits, and flowers.

Is anthracnose harmful to humans or animals?

Anthracnose is not harmful to humans or animals as it only infects plants. However, some people may be allergic to the spores of the fungi that cause anthracnose and may experience respiratory problems if they inhale them.

Can I eat fruits or vegetables that have anthracnose?

It is not recommended to eat fruits or vegetables that have anthracnose as they may be contaminated with fungal spores or toxins. Anthracnose can also reduce the quality and flavor of the produce. If you have no other option, you should wash and peel the fruits or vegetables thoroughly before eating them.

Let us help you

Our most reliable information, advice, tips & tricks for you and your garden

You agree to our privacy policy and to receive emails from Flower Know How which you can unsubscribe from at any time.

Hello nature

Bring your garden inside your home!

Read More

You Might Also Like

Other Articles

More From Flower Know How