I haven't grown zinnias before, but I've heard that they are one of the easiest flowers to grow from seeds. With my seed growing failure rate, I'm needing easy. I'm pretty sure the seed packet instructions were to direct sow outside once danger of frost has passed, but it sounds like you have, or will be, starting them inside? I have two grow light shelving units - one homemade with 4 sets of shelves and one commercial with 3 sets of shelves. I have also accumulated about 8 heat mats. Like most of my gardening pursuits, I obsess and get every conceivable supply or tool, and sometimes have them for years before I actually put them to use LOL. After I've purchased something specifically marketed for gardening, I realize that other general household items work just as well or even better! I think your 8' long under-rug warming mat will work great! So, should I start those zinnia seeds indoors?
