I started 3 different varieties of celery in seed trays with heat matts and plenty of light. I started the first tray on February 9th. of 24 seeds planted, 3 sprouted within 4 days... and that's it. I know celery takes a while, but I am getting close to 21 days now and no real action. On February 22nd I started a back up round of 24, but didn't want to do the same thing and expect a different result (insanity). So this tray I surface sowed. I think I may have gone a little too deep with the original seeds and after some reading, I heard that celery seeds like a lot of light when germinating and some folks got good results from surface sowing. So I gave that a shot. Still nothing. I know its only been 6 days, but the first batch at least had 3 sprout nice and early. Any one able to shed some light on this for me?