Anyone else who use preen on their garden notice it doesn’t stop weeds from germinating? I also have a layer of mulch down and it seems to root in the mulch and not the underneath soil. I did my first application in mid March and there are many weeds coming up now and spent a good amount doing just simple weeding. I thought preen lasts 3 months. I noticed it doesn’t really stop nutsedge or crabgrass, other grasses(found in hay) and garlic mustard