Following on from my guide on growing photinia, I’ve got a couple of lollipop photinias in large pots as well as an established Photinia hedge so I’ve had my fair share of problems with the leaves on my photinias turning yellow and falling off. This can often just be a natural stage in their lives and occasionally, they go through a period of just dropping their leaves.

I have also found with my photinias grown in pots, and I used to see this with pot grown plants in garden centres I have worked at. Not getting enough water (or regular watering) as well as not enough sun can cause the leaves to turn yellow and start to fall. With this in mind, keep your plants well watered, especially those grown in pots and even water in winter during times of minimal rainfall. Also, ensure they are planted in a sunny position that doesn’t get overcast with shade. Ideally, they need around 6 hours of sunshine

On the other hand, it may be the result of infestation by garden pests or by a fungal disease. I cover these issues here which can leave to leaf drop along with what to do about it all.

Normal plant life

Sometimes the photinia will just drop its leaves. If your plant’s leaf drop is a one-time occurrence, prune it back a little bit to encourage stronger growth. They even respond well to hard pruning if needed.

What to do

You may want to apply a slow release fertiliser in the spring, and water it in. Don’t forget to wall plants grown in pots regularly and established plants even need watering during dry spells.

Leaf spot on photinia

Leaf spot is a fungal disease caused by humid and warm conditions. This is a really common issue with photinia. Though it may also be triggered by cold and wet surroundings. It’s not fatal to the plant but the leaf drop may create unsightly bare patches in your plant as they spot spotted leaves look unsightly. Cold wintered can also cause stress which leads to leaf spot. My recommendation is to try and plant them in a sheltered position to help prevent it.

The first sign of leaf spot are red or black spots on the leaves. The leaves then lose their colour, turning yellow, and fall off the plant.

What to do

Remove the leaves that are affected and burn them. If you place them on your compost pile, the disease may spread as it likes a wide variety of plants.

If this leaves a large part of your plant’s branches bare, consider cutting it down quite radically. Photinia comes back stronger and healthier after a quite aggressive pruning so doesn’t worry about pruning them back too hard.

If you can’t change the plant’s current environment to one better suited to it, consider digging up the plant and moving it to a warmer and more sheltered location that has better drained soil. You may want to take some cuttings first, in case the plant doesn’t adapt to its new environment. Read How to grow photinia from cuttings for information on how to do this.

Mites

Unless you have hordes of them, mites don’t do a great deal of damage but its worth just taking a moment to consider. These tiny insects live on the leaves of the photinia and suck the sap from them. This takes the nutrients from the leaves and discolours them. Look closely at the photinia leaves turning yellow for the tell-tale signs of the webs of these insects.

What to do

Spray the leaves with horticultural oil or neem oil and you might want o consider a pesticide if you really have.

Scale insects

Scale insects also damage the plant by sucking nutrients from the leaves. This turns the leaves yellow, and they then die and fall off. The stems of the plant also die back, seriously weakening the photinia.

What to do

It’s important to get rid of scale insects as they leave behind a sticky substance called honeydew which just makes the problem worst. Aphids and ants love this substance and will come flocking to your plant, potentially causing more damage.

Introduce natural predators such as ladybirds/ladybugs and lacewings into your garden environment (believe it or not you can buy these on Amazon). Or carefully use an insecticide, I try to use one for fruit and veg as it is probably safer.

Climate

Backing up a bit, if red leaves don’t appear at all in the spring, the weather may be to blame. The photinia may not have received enough sunlight in its growing period. Additionally, cold weather hurts foliage development, so check to make sure that your plant is in an area that’s not exposed to cold winds.

For information on other problems your photinia may have, and what to do about them, head over to my Photinia pests and diseases article.

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