How to Identify and Treat Agapanthus Diseases

As a child growing up in Delaware, I was always fascinated by agapanthus, a plant I was only familiar with from ogling books filled with pretty pictures of different flowers.

I still vividly remember my excitement on my first trip to California when I saw them growing outside, with their rounded flower heads and long, strap-like leaves.

And now, I am fortunate to live in Zone 9b, where I can grow them in my own garden!

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Agapanthus plants are generally resistant to most pests and diseases.

So resistant, in fact, that if you search the scientific literature for common pathogens that infect them, you mostly find articles relating to their production of antifungal chemicals.

In their native South Africa, scientists study extracts from agapanthus plants as potential controls for a variety of plant diseases.

In our guide to growing agapanthus, we cover how to cultivate these easy-care ornamentals in the garden. They thrive in a full sun location with organically-rich, well-drained soil.

But what happens when things go wrong?

Certain growing conditions can predispose agapanthus to a few diseases, and in this article I will cover five of the most common:

If you are in the habit of reading about plant diseases, there is a good chance you are familiar with anthracnose – a serious disease in plants such as hydrangeas, caused by an ubiquitous worldwide group of pathogens in the Colletotrichum genus.

These fungi are very common in humid temperate climates – waiting to strike when environmental conditions are right. Overwatering and too much moisture on the leaves can