What did you mean by Burpee? That was the brand of seed you used, or you used the Burpee seed starting system? I started plants from seeds for the first time this year. I used the Burpee seed starting kit (tray of 72 soil pellets on a capillary mat, with a water reservoir beneath, no heat lamp, just set next to a window) and had great luck with zinnia (of course), shasta daisy Alaska, and hollyhock. At first, I thought the kit was a huge disappointment, as I got great germination rates but it was almost impossible to remove the seedlings without killing them. What ended up happening, though, was that after mid-late spring, I ran out of steam planting stuff outside, and I just left my seed tray outside, watering regularly. The seedlings continued to grow. Then, I went on vacation for 10 days and so I set the seed tray on the ground in a sunny area where it would get watered by our sprinklers which were on a timer. The plants grew like wildfire! That was early July. I finally got up the energy to plant the plants - the hollyhock seedlings are huge (I never thought they'd finally get big), and I repotted each shasta daisy in a 6" plastic pot leftover from other perennials I bought at a garden center. I now have about 16 plants in such pots - they're growing rapidly and I will plant them in the ground in early August. No, I won't get blooms this year, but I should get them this year. Delayed gratification. The zinnia, it goes without saying, are doing fantastically - if only they were perennials.
I've also just planted purple coneflower seeds directly in the ground per the seed packet instructions, and hope they will come up, as it's very warm out and I am keeping them moist. I know that my other experience won't help you this season, but it's an approach you might want to take next year. When I transplanted seedlings into the ground in spring when the were very small, almost none lived. Now that they are much larger they're thriving after transplant. I wouldn't have thought seedlings would do well growing for 3.5 months in a 1" cell, but they did. I've got over $100 worth of shasta daisies for about $1. Worth it? In the end, yes. Of course $100 isn't all that much and it might have been easier to just buy the plants, but now that the plants are larger and look like they'll survive just fine, I'm satisfied with the effort I put in. I think I'll try it next year. It's an ongoing process. I'm not basing my entire garden on seeds, but since I'm in it for a fairly long haul, I figure I can help fill out my garden cheaply doing some stuff from seed.
Q