This year I placed the pots in the windowsill in the room where I sow my lilies, with the window just open. I guess the temperature might be as low as 10 C / 50 F. After 3-4 weeks the first seedling germinated, and now one and a half months after sowing ( sown 1. January) they look like this:
In the blue pot there's a lot of seeds from a hybrid of rosthornii pollinated with pollen from Awesome and other trumpets. Every day new seedlings appear. The other are maybe from rosthornii or the hybrid.