Nandina suddenly sick
Two, 20+yo Nandina, one on each side front door. Always have been healthy. Two days ago fine. Today, plant on left- loads of green leaves on ground; back third leaves light brown polka dotted, drier to touch; green and brown leaves falling when touched. Adjacent cherry laurels professionally sprayed 5/31 with Talus for scale. Help, please! Thank you.
Update: Nandina on other side dropping green leaves!
Leaves shedding like this can be a symptom of water stress. How is the drainage in the area of the Nandina? Is the soil irrigated/excessively wet -- or has it been very dry? All you can do is prune out the dead stems during dry weather.
This is an invasive plant in Maryland (now regulated as a Tier 2 invasive by the Maryland Department of Agriculture). If the pruned plant does not push out healthy stems, we encourage you to replace it with a non-invasive species. https://mda.maryland.gov/plants-pests/Pages/maryland_invasive_plants_prevention_and_control.aspx
These plants have been in the same spot, through drought and hurricanes, for decades and this never has happened. They were doing great until t his week. I wondered if the Talus treatment for the adjacent cherry laurels, focussed low so I suspect some got into the soil, could be the culprit.
We looked over your photos and discussed your question again this morning. Our thought is that the damage to the nandina is not related to the Talus application. Prune out the damaged area and see what happens. Also, check around the base of the plant for vole damage and soil moisture. If there is mulch around the base of the shrub pull it back so it is not packed underneath the plant.
We have had an unprecedented amount of rainfall over an extended period of time and many established plants are suffering root problems.
See the following information about voles, which gnaw at the base of plants causing stems to die.
Thank you so much for your extended attention to my question! I'm relieved that attending to the cherry laurel's new issue likely didn't create this one. Over the weekend, I pruned back the dead wood and cleaned away the fallen leaves. The bed is mulched and I will push it back at the base of the bushes. I had never heard of voles, nor have I seen them (unless they can look an awful lot like the resident chipmunk we have) or their tunnels.
Thanks so much again,
Usually, you don't see the voles. If you notice silver dollar sized holes in the mulch that is a tell-tale sign you may have them. Typically folks notice plant damage before they know they even have them.