Hardy hibiscus

Question: I have some hardy hibiscus in my back yard, and all of a sudden I noticed this, I’m attaching pics.  I didn’t notice it a few days ago, and I did spray Off near it the other day, so I’m wondering if it could be overspray.  The closest I can find in diseases is rust, but it doesn’t have any kind of growth on it at all, just discolored and curled leaves.  So I’m thinking it isn’t rust.  What can I do for it?  It is worst on this one plant, the other one only has a couple of leaves like this.  And it is all on one side of this p,ant, which is why I’m wondering about overspray.  Help!

responder: An Ask Extension Expert Replied July 21, 2024, 3:25 PM EDT
response: Thanks for your question. Is the affected side of the plant close to where you sprayed the Off?  Also, were any other nearby plants also affected? Looking forward to your response. Thanks for using our forum

responder: The Question Asker Replied July 21, 2024, 6:59 PM EDT
response: Yes, it was right next to where I sprayed the Off.  I don’t think there were any other plants affected, but that plant is on one side of a bench and the other hibiscus is on the other side of the bench and it just has a little bit like that, a few leaves.  But I’m pretty sure I sprayed that way when I put the off on.  No other plants right next to it, just opposite from where the bench is, and they’ve are kind of farther away. MichelleSent from my iPad On Jul 21, 2024, at 2:25 PM, Ask Extension <<personal data hidden>> wrote:   ﻿

responder: An Ask Extension Expert Replied July 21, 2024, 7:20 PM EDT
response: Thanks for your question and response. I strongly think that you are seeing the effects of OFF on your hibiscus. The active ingredient in OFF is something called DEET. In and by itself, DEET should not affect hibiscus. The problem is that DEET is dissolved in various solvents (e.g., hydrocarbons) that are extremely volatile and can form microscopic droplets upon their release from the can. I believe that these solvents have damaged your hibiscus. It is much like herbicide drift with one important difference. In herbicide drift, the herbicide affects plant tissue. In your case, the carrier hydrocarbons affected your plant. These hydrocarbons can lead to the rupture and breakdown of plant cell membranes. This was the cause of the blackening of the leaf in your picture. I’m reasonably sure that the hibiscus will survive and not suffer from any permanent damage. Remove all damaged leaves but try to leave the branches intact. I believe that only leaves have been affected and not the hibiscus branches. Pick up any hibiscus leaves that may have fallen to the ground. Discard these leaves in the trash. With a gentle spray using a hose, rinse the entire plant two to three times daily for the next week or so. It is impossible to know if new foliage will grow to replace what you have removed. Given the lateness of the season now (late-July), I rather doubt that this will occur. However, I have reasonable confidence that such replacement foliage will be seen in 2025. Good luck. Please get back to us with any additional, related questions. Thanks for using our forum.

responder: The Question Asker Replied July 21, 2024, 9:19 PM EDT
response: Thank you so much!  I appreciate the quickness of your reply.  We had a good hard rain this morning, so hopefully that helped too.  I’ll do as you suggest and keep my fingers crosseD!  Now I know!!  It won’t happen again.  Thanks again! MichelleSent from my iPad On Jul 21, 2024, at 6:20 PM, Ask Extension <<personal data hidden>> wrote:   ﻿

responder: An Ask Extension Expert Replied July 21, 2024, 10:17 PM EDT
response: Glad to be of assistance. Don’t dwell too much about things. As I said, I believe your plant will get through this. Thanks again for consulting us.