Rhododendron ponticum · Shrub
Bud blight (Pestalotiopsis): Prune out affected growth in dry weather and avoid overhead watering to reduce humidity.
Powdery mildew: Improve air circulation by thinning dense thickets and apply a suitable fungicide if severe.
Root rot (Phytophthora): Ensure well-drained soil conditions and avoid waterlogging; remove severely infected plants.
Slugs and snails: Use physical barriers like copper tape or apply iron phosphate-based slug pellets.
Budworm (Coleophora rhododendrella): Monitor for webbing in late spring and prune out infested buds before larvae emerge.