Hi Kristine,

Thank you for contacting the UNH Cooperative Extension Infoline with your concerns about the green worm that is infesting your blueberry plants and your rose of Sharon shrubs.

As we discussed, sending photos of the worm to the Infoline will help to identify the pest which then would provide a proven method on how to manage it.  I have included a link to a fact sheet that describes how best to share photos with the Infoline.

https://extension.unh.edu/sites/default/files/migrated_unmanaged_files/Resource007766_Rep11371.pdf

I have also included a link to the UNH Insect Identification Lab webpage which provides information about how to submit an insect sample.  There is a fee.

https://extension.unh.edu/agriculture-gardens/pest-disease-growing-tools/insect-other-arthropods-identification

I have included a link to a fact sheet about the blueberry stem borer because in the larval stage of its life cycle it does resemble a worm.  The fact sheet discusses how to manage the insect.

https://extension.unh.edu/sites/default/files/migrated_unmanaged_files/Resource002142_Rep3156.pdf

The blueberry fruit fly has a stage where it resembles a maggot.  It is not green and is less worm-like but I have included a link to the fact sheet for elimination purposes.

https://extension.unh.edu/sites/default/files/migrated_unmanaged_files/Resource007376_Rep10617.pdf

https://ipm.cahnr.uconn.edu/blueberry-insect-pests-management-review/  This fact sheet describes various pests of blueberries.

A rose of Sharon plant is not a rose but a hibiscus.  I have included a link to a fact sheet that discusses the hibiscus sawfly which in its larval stage resembles a green worm.

https://extension.umd.edu/resource/sawflies/

I hope this information is helpful.  As we discussed on the phone, it is best to identify the pest before spending money on pesticides that may not be targeted for the pest you are trying to manage.