Today I planted some seeds in little cell packs: Blue Bedder Salvia, Painted Daisy, Butterfly weed and Dahlia. I had a hard time trying to plant the little Salvia seeds, so I used a single ply of tissue to lay the seeds on and that worked great to aid in seeing just where I placed them in the little cells. When I finished with the planting I placed the cells in the trays they came with, then placed one on top to hold in the moisture. My trays were opaque, not clear, so I am wondering if that will make a difference.