Planterra Conservatory, Metro Detroit This place is like the Royal Park Hotel conservatory, but on steroids. It's a HUGE conservatory and it is absolutely breathtaking. Planterra provides all floral arrangements, and they are unique and gorge. The max occupancy is 200 so I don't know what that looks like for your guest list. I noticed on the terms and conditions page that music may be limited to a certain level of loudness. I don't know what the typical policy is on that.