Ellen from Dugspur, Va writes
If so, what would be the mix, and how often should I spray the iris?
I've linked a detailed article and study done by the state of Minnesota on this pest for you below. It goes over what to look for and when throughout the year, and what to do to control or stop borers in the iris rhizomes. The treatments are not done in the fall/winter but in the spring and when you see activity of damage starting at the leaves and top parts of the plant since that is where the insect actually enters the plant from, not from the soil. The article goes over when to treat and I've linked to options for spraying if needed.
Iris Borers
https://extension.umn.edu/yard-and-garden-insects/iris-borers#:~:text=Iris%20borer%20caterpillars%20(Macronoctua%20onusta,entire%20plant%20dies%20very%20rarely.
Captain Jacks Deadbug Brew Concentrate
https://www.domyown.com/captain-jacks-deadbug-brew-concentrate-p-1527.html
Spinosad Ready to Spray (hooks to hose)
https://www.domyown.com/spinosad-landscape-and-garden-insecticide-rts-p-1718.html
Answer last updated on: 08/13/2024