Good to see that result, Øystein! Don't forget to post pics next season, too!
I have also tried the reverse cross - L. 'Kentucky' x L. lancifolium var. flaviflorum. I did it three times in two different growing seasons. Kentucky as the pod parent does not produce seed. I remember reading somewhere afterwards that Kentucky is not egg fertile, and I thought to myself: "So it's not just me".
I don't know if this applies to all LA hybrids, though.
