Kykuit is well worth seeing. They run a couple of different tours with different emphasis. I don't think they still do the first tour we did when it first opened, so I won't give tour advice. However, tours do sell out, so keep an eye on that.

From south to north, east side of river. I'm a bit vague on the order in Westchester, since I live in northern Dutchess.

Bronx
Wave Hill

Westchester and Putnam
Kykuit
Sunnyside
Philipsburg Manor
Van Cortland Manor
Lyndhurst
Boscobel

Dutchess Co.
Samuel Morse Estate
Home of FDR
Vanderbilt Mansion
Mills Mansion
Wilderstein
Montgomery Place

Columbia Co.
Clermont
Olana

Not a home or a garden, but there's a new pedestrian bridge walkway over the Hudson, open in 2009 I think. I've never been there, but would certainly visit it if I still lived in NYC. It depends on how you feel about rivers and boats (and many pedestrians and bicyclists), but there's something thrilling about looking up and down a river rather than just across it. A very different perspective.

It may be too far north for you, it's near Poughkeepsie.

Walkway Over the Hudson State Historic Park

Walkway Over The Hudson

Claire

Thanks, we did that walkway about a month ago and I was freaked out by it. I can't take heights anymore and don't know why. I walked out just about to the shoreline below and could not go any further.

We decided on Kykuit and I took your advice and bought the tix for the grand tour ahead of time. I'm glad you said to do that because the morning tour was sold out and there were only 3 tix left for the afternoon tour. THANKS SO MUCH!!!!!

Happy it worked out for you :-)

The Hudson River Valley has one of the greatest collections of historic homes and beautiful gardens in the US. Perhaps only Philadelphia and the Delaware Valley can come close--and they don't have the Hudson River that inspired America's first great art movement. A month there would not be enough. Mad_Gallica gave a good list and there are some excellent books on the subject.

But Kykuit would be my first recommendation for someone with limited time. Boscobel, Montgomery Place (if open), Stonecrop Gardens...just a few.

It's so near that any New England garden lover should plan to visit. Lots of great restaurants, shops etc too if that's your thing.

Montgomery Place does seem to be open. The grounds are unquestionably open, and the house seems to be doing regular tours. I spent the afternoon there today. The gardens need quite a bit of help, but are still there.

I hope to make a trip to the Hudson Valley in the spring. So far, I plan to include Boscobel and Lyndhurst. What would be the best time to visit the gardens?

Mid-June is good. It's quite cold in the Hudson River Valley and takes a bit of time for gardens to get going. I have been at this time and all was glorious.

It depends on what you want to see, what time is best. Most gardens are designed to put on a show any time between late May to first frost. There are a couple, like Stonecrop that have large spring bulb plantings that are worth seeing earlier.