Arbutus: diseases and treatments

The septoria leaf spot of the Strawberry Tree

The most common disease known for the Strawberry Tree is septoria leaf spot, a fungal disease caused by fungi. While it does not kill the tree, its related damage affects its aesthetic appearance and can diminish its vigour and compromise its fruiting.

Causes

This leaf spot disease is a fungal disease caused by a fungus (Septoria unedonis) that initially leads to the appearance of spots on the leaves, followed by leaf decline.

Symptoms

Attacks occur when the weather is mild and rainy, typically in summer and early autumn. The first symptoms of the disease appear during winter.

Brown to brown-reddish round or oval spots, sometimes dotted with small black points responsible for the outbreak, are visible on the leaves. They can spread until the leaf completely dries out, yellows, wilts, and falls prematurely. The fungus can contaminate the entire foliage, leading to widespread leaf drop.

What to do about it?

As a preventive measure

• Preventively, in autumn and late winter, spray the foliage every 15 days, once or twice, with bordeaux mix. Repeat if necessary.

As a curative measure in case of an attack

Initially, to prevent your strawberry tree from completely defoliating and to avoid a proliferation of the outbreak the following year, it is essential to limit contamination. This fungus is likely to spread to other plants, so it is better to be cautious!

• Collect and burn fallen and contaminated leaves to destroy the fungus
• Remove those that are spotted and ready to fall
• Treat at the first symptoms possibly with an appropriate fungicide or with bordeaux mix on the remaining leaves

If your Strawberry Tree is affected by septoria, limit contamination by removing diseased leaves

Aphids

In the beautiful season, aphid attacks are common on the Strawberry tree.

In spring and summer, aphids tend to invade fruit trees, particularly the leaves of Strawberry trees. How can you combat these pests?

Symptoms

Leaves become distorted, curl up, and then turn yellow. Aphids excrete a sticky substance that encourages the appearance of a sooty powder, known as sooty mould, which is actually a black fungus.

Preventing the Attack

• Plant in a part of the garden plants like nasturtiums that are known to reliably attract aphids, which will leave the leaves of the Strawberry tree alone, as they act as a diversion!

In Case of an Attack

• Treat by spraying the foliage, initially, with water mixed with liquid black soap at a rate of one tablespoon per 1 L of warm water. If aphids are still present a few days later, repeat the operation or treat with a natural insecticide based on pyrethrum.