Q.caring for shrub red tip photinia
My son cut all 8 of what became trees. They had not been trimmed for 9 years. Now the stumps have all new growth with that disease and I’m not sure what to do with them or how to keep them trimmed.
Certified GKH Gardening Expert
Prune photinia sometime during early spring through early fall--late spring, early summer being the best time. Unruly plants can be cut back 6 inches to the ground and will come back--annual pruning will help keep them maintained and manageable. They can take a pretty severe pruning, so you can cut them back to a manageable size without harming them.
As for disease issues, photinia red tip is very susceptible to the fungus leafspot, called Entomosporium, that can defoliate photinia plants. Plant photinia in full sun and provide good air circulation. Remove and destroy fallen leaves,prune off diseased twigs. Avoid overhead irrigation. Fungicide sprays (such as copper-based products or neem oil) are also generally necessary for this disease, beginning from bud break and applied every ten to fourteen days until al lfoliage has matured. Mature foliage is no longer susceptible to infection.