Good info, Pod. I have tried this and it seemed to work very well, germination was quick when I nicked and soaked the seeds in a little water and drop of hydrogen peroxide. But I admit I usually just throw them in the soil in late spring and keep it moist.
I've also found that they like the soil warm. Not a good choice for wintersowing, I don't think. But your soil should be warm enough now, Chelle?
Sadly for me, I am pretty much only successful growing nasturtiums in a pot that I can move to a shady location when it gets too hot. On the plus side, I can move it into the garage or sun room over winter and have a head-start on next year. lol
p.s. ~Chelle, sorry! somehow I missed your post up there on the 18th! Not sure what happened.