(November) On my Rose-of-Sharon plants this year, I saw lots of orange and black
bugs that have been identified as assassin bugs. Now, the bugs are still there
and I am wondering what they are eating? My plants did not do well this summer,
and many of the buds did not open. Do you think the bugs caused this and will I
need to spray next spring? If so, with what and when?
I really don't think you had or have assassin bugs. They tend to fly solo-not congregating together, and they would do no damage to a rose-of-Sharon. They tend to eat other bugs, and are actually considered beneficial. I think it is more likely that you had some other insect, possibly box elder bug, which can cause some damage. I would practice good sanitation this fall, removing the falling leaves and old mulch. Start the season off clean, and then monitor the plants. I would not recommend a preventative spray for insects, but if anything reappears, take a sample to your extension office and spray as needed.