My Japonica is Being Attacked! - Ask Extension
I'm writing about a Japonica I planted 2 years ago at my boyfriend's house. I was monitoring it now and then over the winter and it appeared to be doi...
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My Japonica is Being Attacked! #823707
Asked March 28, 2023, 11:35 AM EDT
I'm writing about a Japonica I planted 2 years ago at my boyfriend's house. I was monitoring it now and then over the winter and it appeared to be doing fine, but I hadn't checked it in probably a couple or 3 weeks ~ now I've realized that was a big mistake! Something is attacking it ~ hope you can help me with information about what you think it might be, and how to treat it. Thanks for any help you can offer!
Franklin County Ohio
Expert Response
Pieris japonica can be affected by several diseases like Leafspot, dieback and Phytophthora root. As well as a couple of insects like Nematodes and Lacebugs.
Following is a link to a Univ Extension site with more info about Lacebug damage. https://extension.umd.edu/resource/lace-bugs-trees-and-shrubs
Environmental factors can cause similar problems. This plant prefers to grow in partial to full shade site. If it is in full sun, consider moving to a shadier spot. It can suffer if it is not protected from winter winds and does not like to be planted in a low lying area that may collect water.
You might also consider a soil test. This plant cannot tolerate alkaline or neutral pH soils. The iron deficiency causes chlorosis and poor health and so it prefers an acid soil pH of 5.0 to 7.0. Following is a link to an OSU Factsheet on Soil Testing that lists labs that perform soil tests. NOTE: Michigan State (MSU) no longer performs soil tests. https://ohioline.osu.edu/factsheet/hyg-1132
You can also send a leaf sample to the OSU Plant & Pest Diagnostic Clinic for analysis. Following is a link to that site:
https://ppdc.osu.edu/submit-sample/landscape/woody-ornamental-plants
Following is a link to NC Extension with more info about Pieris Japonica https://plants.ces.ncsu.edu/plants/pieris-japonica/
Following is a link to a Univ Extension site with more info about Lacebug damage. https://extension.umd.edu/resource/lace-bugs-trees-and-shrubs
Environmental factors can cause similar problems. This plant prefers to grow in partial to full shade site. If it is in full sun, consider moving to a shadier spot. It can suffer if it is not protected from winter winds and does not like to be planted in a low lying area that may collect water.
You might also consider a soil test. This plant cannot tolerate alkaline or neutral pH soils. The iron deficiency causes chlorosis and poor health and so it prefers an acid soil pH of 5.0 to 7.0. Following is a link to an OSU Factsheet on Soil Testing that lists labs that perform soil tests. NOTE: Michigan State (MSU) no longer performs soil tests. https://ohioline.osu.edu/factsheet/hyg-1132
You can also send a leaf sample to the OSU Plant & Pest Diagnostic Clinic for analysis. Following is a link to that site:
https://ppdc.osu.edu/submit-sample/landscape/woody-ornamental-plants
Following is a link to NC Extension with more info about Pieris Japonica https://plants.ces.ncsu.edu/plants/pieris-japonica/
