I have a case of onion plants to transplant and wondering about which preemerge to use. In 2017 I used Outlook applied like two weeks after transplanting. The info that came with the plants recommends Treflan but they are talking about the granular product for home gardens I am pretty sure. I have the old 4 EC product. I don't find the labeling for using that. Be good if I had a product to use before transplanting if I can.