winterberry pest - Ask Extension
up to this season healthy winterberry shrubs
leaves are eaten and developing berries are turning black
I have cleaned the beds, cut scrubs to provi...
Knowledgebase
winterberry pest #878002
Asked July 20, 2024, 10:17 AM EDT
up to this season healthy winterberry shrubs
leaves are eaten and developing berries are turning black
I have cleaned the beds, cut scrubs to provide air, and sprayed with NEEM
Anything else I should do?
Thank you!
Montgomery County Maryland
Expert Response
Winterberry is a great native shrub and we are glad you are growing it. It is also a pretty tough plant with few problems.
Here is our page on it:
https://extension.umd.edu/resource/winterberry-holly/
You need not be concerned about the issues you are seeing, especially if the plant overall looks well, which it seems to be.
Plants in our landscape don't have to have perfect leaves. They make many more than needed, and as a native plant, it has evolved for eons in harmony with other flora and fauna that support each other.
The leaf chewing could be related to beetles, perhaps one of the night feeders but the damage is minor.
As far as the berries go, many plants can abort some developing fruit if stressed. Winterberry is happiest in wet or moist conditons and in this case we'd suspect the problem is very high heat and prolonged lack of rain, approaching drought conditions this season. (Interesting fact: during periods of high heat, the flower sets of tomatoes and peppers that bloom during very high heat are rendered infertile and will not produce fruit.)
We do not recommend any further spraying. In general it is rarely needed. Under high heat conditions it can actually burn foliage, and Neem can hurt non-target beneficial insects as well.
Christine
Here is our page on it:
https://extension.umd.edu/resource/winterberry-holly/
You need not be concerned about the issues you are seeing, especially if the plant overall looks well, which it seems to be.
Plants in our landscape don't have to have perfect leaves. They make many more than needed, and as a native plant, it has evolved for eons in harmony with other flora and fauna that support each other.
The leaf chewing could be related to beetles, perhaps one of the night feeders but the damage is minor.
As far as the berries go, many plants can abort some developing fruit if stressed. Winterberry is happiest in wet or moist conditons and in this case we'd suspect the problem is very high heat and prolonged lack of rain, approaching drought conditions this season. (Interesting fact: during periods of high heat, the flower sets of tomatoes and peppers that bloom during very high heat are rendered infertile and will not produce fruit.)
We do not recommend any further spraying. In general it is rarely needed. Under high heat conditions it can actually burn foliage, and Neem can hurt non-target beneficial insects as well.
Christine
