🌿 Photinia Leaf Spot (Entomosporium Leaf Spot)

Overview

Photinia leaf spot is a common fungal disease in the UK, particularly affecting Photinia × fraseri 'Red Robin'. It thrives in the UK's cool, damp climate, especially during spring and autumn. While not immediately fatal, repeated infections can weaken plants, leading to significant leaf loss and reduced vigour.

Affected Plants

In the UK, the disease predominantly affects:

• Photinia × fraseri 'Red Robin'

• Other Photinia species

• Indian hawthorn (Rhaphiolepis indica)

• Loquat (Eriobotrya japonica)

• Pyracantha (Firethorn)

Symptoms

• Small, circular red or purple spots on young leaves

• Spots may enlarge, developing grey or tan centres with red margins

• Severe infections can cause leaves to yellow and drop prematurely

• Repeated infections lead to sparse foliage and reduced plant vigour

Management Strategies

1. Cultural Controls:

• Pruning: Avoid pruning during wet conditions. Prune in dry weather to improve air circulation and remove infected material.

• Sanitation: Regularly remove and destroy fallen leaves and pruned material. Do not compost infected debris, as this can spread the fungus.

• Watering: Water at the base of the plant to keep foliage dry. Avoid overhead watering, especially during humid conditions.

• Site Selection: Plant Photinia in full sun and ensure good air circulation. Avoid overcrowding and planting in shaded, damp areas.

2. Chemical Controls:

• Fungicides can help prevent new infections but won't cure existing ones. Apply a suitable fungicide during periods of new growth, following the manufacturer's instructions.

3. Alternative Planting:

• If Photinia continues to suffer despite management efforts, consider replacing it with more disease-resistant alternatives such as holly (Ilex aquifolium) or laurel (Prunus laurocerasus).