Wild Bergamot rotting?

Question: Had a conservation landscape thing installed this spring. I’ve been watering for a while. The plants are growing really well. I have a bunch of wild Bergamont. I’ve started to get very sickly looking with the stocks, splitting brown and bumpy. Anything I need to be concerned about or is this dress from the stress of lack of water this spring.

responder: Answered by the Home and Garden Information Center (HGIC), University of Maryland Extension. For timely gardening information and tips, subscribe to our Maryland Grows blog and quarterly newsletter. Follow us on Facebook, Instagram, and YouTube. Replied June 20, 2023, 9:15 AM EDT
response: The foliage of the Bergamot appears to have some powdery mildew, but the infection looks relatively mild and it's a very common disease on this and many other native and non-native plants alike. Treatment is not necessary and this won't impact its pollinator value much. The dark bumps on the lower stem are adventitious roots and not rot. These are root "primordials" (tissue that can develop into roots if conditions are suitable) and can be stimulated to form by wetness or high humidity, so you may want to make sure the plants are not staying too wet. Water thoroughly if the soil feels somewhat dry to the touch about five or six inches deep, but if damp when checked at that depth, watering should not be needed. Water only the soil/mulch surface so the leaves and stems are not wet-down, but if that's unavoidable, then water early enough in the day so that the plant surfaces can dry by nightfall. It won't hurt the plant if these root buds develop into roots, but otherwise their presence above the soil line suggests things might be getting too wet too often.  Miri

responder: The Question Asker Replied June 26, 2023, 4:21 PM EDT
response: Hi Miri- thank you for the response.  I wasn’t concerned over the powdery mildew at all but just at how many bumps there were and splitting practically of stems.  I suppose my worry is that the coreopsis also has strange growth patterns.  Can you see below from the company that did the installation- is it possible there is a virus? Attaching pics of some of the other plants.The company who did the installation had also come out and this was her response:I am not sure what is going on. It looks like a virus possibly but it's odd that it's happening to several species- I saw some odd growth on the iris and the monarda too. Any word from the Master Gardeners? I am wondering/worried about possible compost contamination. I've never run into this before. I'm still thinking it through. Please keep me posted on any new developments and if you hear from the master gardeners.Thanks again for taking the time to review! On Tue, Jun 20, 2023 at 9:15 AM Ask Extension <<personal data hidden>> wrote:

responder: Answered by the Home and Garden Information Center (HGIC), University of Maryland Extension. For timely gardening information and tips, subscribe to our Maryland Grows blog and quarterly newsletter. Follow us on Facebook, Instagram, and YouTube. Replied June 28, 2023, 10:08 AM EDT
response: While we can't rule-out virus because there are so many types of plant viruses, this appears to be herbicide damage. Was any type of weed killer/preventer used in the nearby lawn or in the flower bed itself in the weeks/months prior to the symptoms appearing? Depending on which chemical might be involved, because herbicides work in different ways, they can cause stem curling and leaf deformities plus adventitious root growth.  If this is herbicide exposure, the deformities can't heal (and the adventitious root formation probably won't hurt anything) but the plants may be able to eventually outgrow the damage and look normal again. Time will tell, as there is no antidote to an accidental exposure. If you did not apply herbicides, perhaps a neighbor did and some spray drifted over onto these plants, if the next yard over isn't very far away or the weather was too warm or breezy when an application was being made.  If none of the above seems plausible, could any new mulch or compost added to this bed this year have been tainted with herbicide? (Some bagged mulches contain pre-emergent, though they are labeled as such; some animal manure composts might contain herbicide residues that did not break down.)  Miri

responder: The Question Asker Replied June 28, 2023, 11:33 AM EDT
response: Thanks. I don’t use herbicides at all but I think my neighbor had an application but would have been a few weeks before my installation. I’ll share this with the contractor and see what they know about the compost. I will hope for the best long term.  So disappointing!!On Wed, Jun 28, 2023 at 10:08 AM Ask Extension <<personal data hidden>> wrote:

responder: Answered by the Home and Garden Information Center (HGIC), University of Maryland Extension. For timely gardening information and tips, subscribe to our Maryland Grows blog and quarterly newsletter. Follow us on Facebook, Instagram, and YouTube. Replied June 28, 2023, 4:22 PM EDT
response: You're welcome, and good luck!