The Bellagio Conservatory is a vast greenhouse-and-flower display just past the lobby, refreshed five times a year with elaborate themed installations: giant fabric butterflies for spring, a snow-dusted village for winter, animatronic dragons for Lunar New Year. Around 8,000 to 10,000 fresh stems are used at any one time, replaced every two weeks to keep everything looking new.
It is free to walk through and runs 24 hours a day. Crowds peak between 10 am and 5 pm; come early or late if you want a clear path to take photos. The conservatory is one of the genuine reasons to walk through the Bellagio even if you do not stay or gamble — it is a clever solution to a casino architecture problem (a generous, beautiful, free space that draws people inside without selling anything).