Hi curios:
Thanks for the feedback. I used only dry granular merit last year, and got many borers. This year with the combo: dry + liquid, I got very few borers. Looks like you have to do both liquid with dry to get good results.
Anyone else out there use Merit (as a combo application or dry/liquid alone) and can report back on the results?
Thanks,
Laetiita

I continue to have excellent borer control with granular Merit alone, applied in early spring just as irises break dormancy and begin active growth. I sprinkle 1 tsp. of Merit (Bayer Advanced Lawn Season-Long Grub Control) by hand around and over each iris clump, regardless of clump size. I do not broadcast Merit granules as I feel it's extremely important to make sure each plant gets its full dose. I don't bother to scratch in the granules, though that would probably be advisable. It is very important that the granules be thoroughly watered in, either through natural rainfall or sprinklers, or they will be ineffective.

Laurie

After digging up Iris and treating the soil with detergent water, can you plant a different kind of plant in that spot or should I leave the area alone until next spring?