The common ditch lily or Hemerocallis fulva 'Europa' is a triploid and more or less sterile both as a pod and a pollen parent. If one hand pollinates hundreds of tetraploid flowers with the pollen from 'Europa' one might get a few seeds. There would be more seeds from those crosses than similar crosses using diploid daylilies as the pod parents. Probably all of the seedlings that might develop from those seeds will be triploids.
'Europa' is self-incompatible. Stout determined this; it is not self fertile.
