Mindrunner> Actually it's really easy to bloom girls on DMM. There is a ton of free blooming stuff. Blooming hearts cost only 150 Life Crystals and you know how it's super easy to get Life Crystals on DMM (but it's harder to get Bloom affection gifts...).
I'm totally F2P and I got 5 bloomed girls and 4 with bloomed affection in... two months? Something like that.
I don't really see any link between blooming and F2P or not (aside the amount of 5*/6* owned).