Pieris Plant Problems – What to look out for and how to treat them
Our site is reader supported, this means we may earn a small commission from Amazon and other affiliates when you buy through links on our site.
The pieris plant isn’t too difficult to look after if you take time to understand and follow through on its location, soil, and sunlight needs. However, even in the most cared for gardens, pieris plant problems do occur. With pieris shrubs, they’re usually related to pests, disease and how you’re caring for the plant.
At some point you’ll probably come across the pieris lacebug – named after the shrub. It survives by sucking out the sap from the leaves. You should periodically check your plant for signs of this bug and act immediately to eradicate it. This is one of the most common pieris plant problems.
See my article Pieris Leaf Problems for details on how to find and recognise this bug and how to treat it.
The most common disease found on pieris plants is fungal root rot. This develops when fungal spores from the air find a warm and moist spot on your leaves to develop on. I’ve written about how to recognise and get rid of this disease in the Growing Pieris Forest Flame article.
You may also come across Phytophthora Root Rot, though it’s a fairly rare disease. This affects the whole plant so it’s quite noticeable. See the article Pieris Forest Flame Diseases for more information about this, but know that it’s a fatal disease for your shrub.
Poor maintenance of pieris
Beyond pests and disease, the main pieris plant problems may be due to how you’re looking after it.
Lack of nutrients
Pieris plants need an acidic soil. If your leaves are a sickly yellow colour instead of the glorious shades of red, cream and green that you expect, check your fertilising plan. Choose organic mulch or a commercial fertiliser developed specifically for acidic plants. If you’re unsure what to buy, choose one that’s for azaleas or rhododendrons as these other plants have the same requirements as pieris.
If you’re trying to grow your plant in alkaline soil, you need to fertilise it regularly. The shrub uses up the nutrients that you feed it to keep it acidic and then needs more. If you don’t have acidic soil in your garden, consider growing the shrub in a container where you can use ericaceous a compost to give it the best environment.
Too much sunlight
Sickly leaves may also be due to too much sunlight or too much sun at peak times (11am to 2pm). The pieris plant comes from a mountainous region and isn’t used to direct sunlight. Plant it where it gets some shade. Dappled shade is best. Or erect a screen of trees or some kind of a fence or trellis, you could even make it a feature in your garden) to keep much of the sunlight out.
Rootbound in a container
Pieris shrubs grow successfully in containers, especially the compact smaller ones of the Pieris Japonica variety. However, they can become root bound and you may notice this through a lack of flowers. If you pick up the pot and notice that roots are making their way through the drainage holes, you’ve got a problem.
You need to carefully report the plant into a larger container. Use fresh compost and regular feeding with ericaceous feeds to get the plant over the shock of being moved. This also gives it the nutrients to become established again.
Of course, if you have a very young pieris plant, it may not be mature enough to flower yet!