Marianne's Response

Why are leaves falling from pieras japonica?

I have five Flaming Silver pieras japonica. Last summer they had what I think was a lace leaf or some type insect and I used some insecticide spray and they all recovered and did well after that. Now there is lots of pretty new growth but most of them have many leaves that appear to turn yellow and then brown and fall off. I don’t see any black spots on the leaves. I wondered if they just need some fertilizer and if so what type? Or maybe this is normal? They are on the north side of the house and get morning sunlight and a few also get afternoon sunlight. They are about 10 years old.
Photos attached.
Thank you!

Posted by Ruth Faldet on April 27, 2025

Marianne's Response

I have some good news. Based on the healthy new growth and dried brown leaves near the Pieris plants I predict these shrubs will make a comeback and are just dropping last year's leaves quickly due to the past infestation. I do not suggest fertilizer as fast new growth is more susceptible to another insect invasion. Just extra water this summer during drought and spray foliage with strong jet of water every few days if you see lace leaf mites coming back. Keep growing, Marianne Binetti

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