I have made roses from Fimo before, it's easy:
But I had a bunch of roses that came in some job lot, and I could just as well use them, only they had white stems. Why would anyone make roses with white stems? However, these roses had white stems which I had to paint - which felt a bit Alice in Wonderland.
By the way, I always use dry oasis when I paint small things.
I am pleased with the result:
Of course you can ask: where does this rose actually grow from. The answer is: I don't know. Yet.