Ask Mr. Smarty Plants

According to our Native Plant Database the most northern state that Aesculus pavia (Scarlet buckeye) is native to is Virginia.  Michael Dirr, in his Manual of Woody Landscape Plants: Their Identification, Ornamental Characteristics, Culture, Propagation and Uses states that it is native from Virginia to Florida and hardy in Zones 6 to 9.

So the real question is, why are your friends' plants blooming?  In Niagara Falls you are in Zone 6 which means that the plant will survive your winter, but you are definitely out of the native range of the plant.  There is something about the conditions in which the other plants are planted that are more favorable than yours and you will have to figure out what that difference is.

Ideal growing conditions for the plant are part shade and moist, loamy, somewhat acidic soil.

Look carefully at where your friends' plants are sited and try to figure out what sort of microclimate they have and see if you can mimic it.  It seems like what you are experiencing is something all northern gardeners do at some point ... when you take a plant out of it's "comfort zone" it may survive, but not thrive.  Because the plant flowers somewhat early in the season, the flower buds are set during the previous growing season.  The buds on your plant are not surviving the winter for some reason.  You can see a photo of a bud at this blogspot. Watch your freinds' plants closely through this growing season and let us know if you figure out what is going wrong. 

Some other hummingbird favorites for your area are:

Aquilegia canadensis (Eastern red columbine)

Ceanothus americanus (New jersey tea)

Lobelia cardinalis (Cardinal flower)

Lonicera sempervirens (Coral honeysuckle)

Monarda didyma (Scarlet beebalm)

Penstemon digitalis (Mississippi penstemon)