I have read several posts dealing with this, and they all said what you have mentioned. I have a garden that I had been working on for a very long time, so long that all my plants have reached perfection. I have since moved them inside a greenhouse after Seasons was added. With that said, my Orchid plant only produces 2 flowers. I have since given up on splicing since seasons because they don't produce the spliced combination, at least in my game they haven't.
Do you have any bees in your sim's garden? The reason I ask is that they do help with pollination.
