Willow Herb Seed Germination

I am having trouble germinating willow herb. It is supposed to germinate easily. Please let me know how you germinate willow herb.

We surface sow the seeds and just press them down into the soil, but we don't cover them with more than the merest sprinkle of fine vermiculite or fine perlite. We water with a mister or you could set the pot into a tray of water and leave it there until the surface of the medium has become moist. Put into a warm, bright spot, but be very careful to not let the surface get dry even once! Any seed allowed to dry out while germinating dies!