Answer: I am not familiar with a tree commonly called a Japanese Snowdrop, but I do recognize Japanese Snowbell (Styrax japnicus). To make sure which tree was addressed on the show, you might want to contact them directly.
Styrax japonicus, according to Michael Dirr's "Manual of Woody Landscape Plants", is hardy from zones 5 through 8 (injured at minus 20) and grows to about 25 feet tall and wide. It requires an evenly moist and acid soil and should be planted in a sheltered location.
In my garden, it is a delicate-looking and graceful plant and blooms in spring with little white flowers facing downward, they are very fragrant. These are followed by green drupes, attractive in a quiet sort of way. There is no fall color to speak of.
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