Photinia Red Robin makes a really photogenic hedge plant, with blazing red young leaves that can be persuaded to reappear all summer with regular trimming and simple but lovely white flowers.
However, just as the most handsome face can be marred by acne, the prettiest Photinia bush can can be disfigured by an unpleasant looking dose of Leaf Spot. It really is an ugly thing to happen to such great foliage and if it comes your way, you may be quite alarmed.
Our advice is to be calm. The first thing to consider is this: Photinia Red Robin loves sun and well drained soil, it also is not a big fan of very humid or very cold weather. If your plants are in a dark, damp place and suffer a harsh winter followed by a muggy summer, their natural defenses will be strained and they will be more susceptible to disease.
Obviously, you can choose the right place to plant them but you can’t control the weather. If your plants are in a sunny, well drained spot and get leaf spot due to bad weather, you have nothing to worry about. If, on the other hand, they aren’t in a suitable location and get severe leaf spot on a regular basis, then you must be brave and replace them with a hardier plant.
There are two possible causes of the spots. One is fairly harmless and only ever occurs after manky weather. The other, called Entomosporium, also needs cold, wet weather to strike hard and is a bit more of a pain. It is very hard to tell them apart.
Fortunately, the treatment for both is the same – remove and burn affected leaves on sight and keep the bottom of the plant ruthlessly clean of fallen leaves – a single decaying leaf can be a springboard for enough spores to affect an entire hedgerow.
Even if you get a few spots coming back, don’t worry, it’s just nature doing its thing. If you have a plague of spots year after year, don’t waste your time on a loosing battle with chemicals and sprays – be graceful and rethink your planting scheme.
And remember – healthy plants tend to stay healthy. Overfeeding can be almost as bad as underfeeding: each year, apply a single dose of liquid feed around the base of your plants, according to the instructions of your product (early spring is usually the best time). If your area has dry soil, apply a bit of mulch around but not touching the stems of your plants in late spring and water your plants if there is a drought.