Photinia Leaf Spot – Don’t Panic!

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.

9 thoughts on “Photinia Leaf Spot – Don’t Panic!

  1. I have a lot of black spot on the newly planted ‘Red Robin’ what can I spray it with?

  2. Most of the leaves on my photinia planted last year have leaf spot,its in a area that only gets sun in the morning what can i treat it with

  3. Hi Ted,

    Last summer was a sucker for mildew and other fungus problems like leaf spot. You mention that your site is shady, is it also very sheltered, with a restricted air flow and/or lots of other plants crowded around the Photinia (these things will make the site more humid and encourage leaf spot)? Which part of the country are you in? What is the soil like, especially in terms of moisture & drainage?

    To kill the fungus, you’ll need a systemic fungicide that works from the inside of the plants. Once the issue has cleared up, you can switch to an organic, preventative, copper based fungicide like Bordeaux mixture. I haven’t used these for Photinia myself, I would advise using organic controls (i.e. cleaning up fallen leaves, pruning & changing the mulch a couple of times a year), but they should be effective.

    If your plants aren’t in a suitable location, i.e. sunny, with a good air flow and not too much soil moisture, then I would suggest replacing them with a more suitable plant, such as an ornamental holly (if you need some intersting leaf colour). If the plants aren’t happy, the leaf spot will just keep on coming and you’ll save yourself time and money in the long run.
    It’s early days and I haven’t seen your site & plants in person, so I don’t want to be too gloomy. If you use sprays for the next couple of years and aren’t happy with the results, whip the Photinia out and start again.

  4. hi

    my problem with the red robin is there are holes in the leaves.when i dig the soil there are some
    worms.also not in the best spot where i put them.

    is there any product to fix this problem.

  5. Worms in the soil are good if they are worms and not slugs or caterpillars. If the holes in the leaves are mainly round and look as if they could have been the result of a being fired at with a shotgun then they are almost certainly fungal. As the weather dries and warms the new foliage will not have these. They are not pretty, but pretty harmless

  6. My photinia obiously has leaf spot and appears to have provided the vine weevil with a meal. Will the dreaded weevil attack the roots or just the leaves? I’m always reluctant to spray or use chemicals but especially here as the two plants are alongside the lavendar hedges planted for the bees.

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