Gerber daisy seeds are tricky, too. The commercial seed I got in last year's swap had great germination. The seeds were elongated, but plumper in the middle. The self collected ones had 0% germination. They were long and skinny, with no plumpness in the middle.
My research uncovered that unfertilized flowers make seeds that have nothing in them, and look okay except that they lack plumpness.
They really need hand pollination to get fertile seeds.
