What an excellent collection!
If you are fond of plants, this collection is very impressive. There are several dedicated rooms including the "Palm House" with some very impressive Palms, the "Desert House" that has some really amazing Cacti and Succulents, and a "Fern House" as well as some other rooms and an outdoor pond area and a very large garden.
This is the longest continually-running Conservatory (right next to the first Aquarium in the US), and it is a "must-see" for plant lovers.
The hours are Wednesday - Sunday, 10 a.m. - 5 p.m, at the time this review was written. I find Wednesday to probably be the best day with the fewest crowds. Usually though, my experience has been that it doesn't get terribly crowded.
Bell Isle is a great place close to the city where you can spend an afternoon. If you have a recreational pass (registration sticker is $11 when you renew to add access to Michigan parks), there is no fee. I believe it is around $9 per vehicle otherwise if you are coming from out of state. Personally, if you live in Michigan it is well worth $11 for access to all of the state parks. But specifically in Bell Isle, the state troopers will fine you if they spot your vehicle without the registration pass or a day pass.
Entrance to the Conservatory is free.
