Last year I used garden safe Ortho Bug B Gone around the perimeter of my patch for grass hoppers, crickets, and other misc. critters. It worked better than nothing. According to the instructions you can use it in your patch and be okay but I put around the outside of the patch to be safe. It might work better if you use it in the patch.
I had so much rain last year my critter control kept getting washed away and I couldn't mow or pull weeds so the grasshoppers just jumped from tall grass to tobacco. They weren't on the ground much to eat the Bug B Gone. You may not have that problem where you live. I hope I don't have that problem again this year. I never could get caught up on critter and weed patrol.