I had to remove all flowerbuds on this Hibiscus 'Blue River II' until I thought they'd coincide with a single induced early flowerbud on Hibiscus grandiflorus. Usually there's around two months difference in bloom time for these two. The induction was accomplished by using an inverted galvanized trashcan every evening to shorten the photoperiod (actually to lengthen the night). From all of this work, I've got several pods ripening now. And 'Blue River II' is so perturbed by all the disbudding that it's STILL flowering even though the foliage is yellowing and dropping for the Fall.
The red arrow in the first picture shows one of the ripening pods. I sure hope I'm able to raise some grandiflorus hybrids from these seeds.
The second picture shows the whole plant going dormant yet still blooming.