I too have had trouble with some seeds. A packet of Mottistone lettuce has refused to grow even one seeding.
I tried them in the heated propagater, the window sill and the greenhouse bench. I tried growing with a covering of compost and on the surface of the compost under a sheet of glass, not so much as one lettuce.
I have never tried this variety before but they looked so good in Charles book I was looking forward to adding them to my salad bowl.
