This is so weird, because I've got pairs of hybrids all sitting on beaches and only one or two of them has ever bred a third flower. I must be doing something wrong here. /scratches head
I know it's possible, but I've had a much harder time breeding hybrids on the beach than in the village. It can be done, but maybe it's not as easy/common?
I've never bred flowers on the beach before, but I've heard that it's easier to do because it prevents villagers from moving onto them. Also, because all of the flowers are in one place, you'll immediately be able to tell if someone has stolen a hybrid or if one has spawned. c: