I may be wrong about this but my thoughts are that if the parents were not compatible, the seed pods would abort or the seeds not be viable. The only kind of incompatibility that I know is different ploidy.

We hybridize with triploid Fulvas. Some varieties will throw tet gametes and will be able to set seed when crossed with hybrid tets. We find that many of the seeds look good, but seem to be empty shells. Every time I check them in the winter for mold and so forth, I find a few more that are bad. Then when planted, the germination rate is not as high as we normally would get.

I don't think incompatibility would show up in the seedlings. Some varieties just produce puny plants.

At what stage did they die? Seedlings are susceptible to damping off. We had a bunch die this season in one tray. I think I used a bag of starter mix that had sat open for a while and wasn't sterile. We use a fungicide to prevent damping off and it usually works well.

I would think the four inch pots would be better for them than the smaller seed starter ones. Daylily's roots like to go deeper than those provide space for. We use a tube that is 6 inches deep to start our seeds.

Nancy

Thanks, Nancy. I appreciate your input.