A plant-covered apartment tower is set to be constructed over a busy suburban train line, in what could become a first for Melbourne.

Developer SMA Projects has announced plans to build a 20-storey skyscraper in Windsor, hovering above the Sandringham Line.

The green building will hover above the Sandringham rail line. Credit:SMA Projects

VicTrack has agreed to sell around 600 square metres of airspace over the railway line, but exactly how much will be paid by the developer remains under wraps.

The future high-rise would be located just 30 metres from Windsor Station, on the eastern side of Chapel Street, and would become the tallest building in the neighbourhood.