It should germinate any time. Old seeds can take a month; fresh should germinate in about 2 weeks.

I tried starting culantro several times. I had absolutly NO success and I've had very good germination rates on most stuff I start. It's a toughie!

Chris

Chris, start the seeds in sphagnum peat when it is warm. Just surface sow it & keep it moist. Even old seeds will germinate that way. That is why the seed company suggests peat pellets. The seed responds to the low pH of the peat. There is decreased germination when it is sown in soil. None of my seeds planted in soil germinated.
I am constantly trying to develop methods for easy & cheap propagation. I had 3 plants last year & their seeds. I got 500 seedlings from the sphagnum method. I had seeds from 2001 germinate with this method. As long as they have room to grow they can stay in that peat a long time  some of mine over wintered there.