Last summer I took NY Waterway's package "cruise" to Kyukit, the Rockefeller estate in Tarrytown, NY. It's an all day thing. You bring your lunch and NY Waterway (see link below) does the rest. I'd say for $60 it was an OK deal, but you don't get much garden out of it. We really enjoyed Philipsburg Manor, included in the tour -- it's a working 17th century colonial farm, and it has an interesting vegetable garden and a corn mill. (We made cornbread from the meal we bought there, and it was very tasty!)

I think the two gardens I'd recommend you visit, along with the ones you mentioned, are the New York Botanical Garden and the gardens at the Cloisters (a branch of the Metropolitan Museum of Art). They're in the Bronx and very far northern Manhattan, in the vicinity of Wave Hill.

Have a wonderful trip!

Here is a link that might be useful: Tours on NY Waterway

Definitely don't miss Wave Hill. Unique plants, lovely setting. One of my favorites.

The EM Mills Rose Garden in Syracuse is just GORGEOUS in the summer. My husband and I go there several times each summer just to get ideas for what roses we want to grow! It is peaceful and well-kept and has a huge variety! (Don't know if you love roses like we do or how close you are). Phyl GalwayGP@aol.com

Innisfree is wonderful and close to the Hudson Valley gardens and Annandale on the Hudson is also beautiful. I second the Cloisters but realize that travelling around the city can be slow so take that into consideration. If you are on Long Island, consider Old Westbury Gardens. The Brooklyn Botanic Garden is especially beautiful during daffodil season. Enjoy.

Don't forget the Bronx botanic garden across the street from the bronx zoo. Brooklyn Botanic is a huge place. be sure to give it enough time.
Martha

Sounds like a great trip!
Since I am a resident of the Hudson Valley, I can proudly recommend the Vanderbilt estate as well as the F.D.R.estate rose gardens which are right down the road from the Vanderbilt...very beautiful.
Have a fun!
Joyce

NYBG is in the Bronx north of Manhattan (there is no Bronx Botanical Garden) Wave Hill is a 15-20 minute drive from NYBG. You can get to NYBG on metro north railway (about 20-25 minute ride from Grand Central) but to get to Wave Hill you probably need to take a taxi from Riverdale or drive.

Brooklyn is south of Manhattan and BBG is probably about a 40-50 minute subway ride from midtown.

Old Westbury Gardens is on Long Island about 35 miles east of midtown off exit 39 on the L.I.E. or by taxi from the Westbury or Carle Place L.I. Railroad stations.

You could do all these in 4 days. If you have a car do NYBG and Wave Hill one day, BBG and Old Westbury another. I think the best times to visit are mid May through June in the NY metro area.

The Waterway tours aren't going to bring you to these gardens but it would be a nice day out!