Upon learning of the upcoming Chicago World's Fair (1893), railroad officials decided that Niles, which was the last major stop before Chicago, needed a grand station to impress east coast travelers and take advantage of the excitement around the fair. This is why the Niles depot was built.
Additionally, to give the depot even more flair, the gardens were included in the plan. To this end, the railroad hired German immigrant John Gipner, who learned gardening in Germany. The depot soon earned a reputation for being the most beautiful station between Buffalo and Chicago, and the city was dubbed the garden city. Gipner even handed out flowers to women passengers.
The New York Central bought the Michigan Central in 1935 and tore down the greenhouses and did not maintain the gardens. The empty field next to the station is where they were located.