Green8, designed by Berlin architects Agnieszka Preibisz and Peter Sandhaus, is a high-rise apartment building in the shape of a twisted figure of eight.
It includes elevated gardens, greenhouses and community spaces and is held upright by cables.
US property investor Hines is currently running a competition to design a 150m-high apartment building – also in Alexanderplatz – but Preibisz and Sandhaus are not taking part in the contest.
Preibisz said: “The architectural discussion is often led by investors saying ‘I want to build something here and make a profit by selling the apartments,’ but ideally we want a cooperative to stand behind our project.
“We would like to found a cooperative to finance the project mostly for people who will actually live in the building and participate in the community.”
The design seeks to meet a growing demand for self-sustaining gardening among city residents. According to the architects’ project description, the building would bridge the gap “between the desire for a pulsating urban life and the craving for a lifestyle in harmony with nature.”
“Alexanderplatz, as the centre of the city, is very much lacking in this kind of living quality,” Preibisz told The Local. “At the moment it’s mainly shopping and its just space. But we want to promote with our concept some new ideas for Alexanderplatz.”
The 48-year-old architect added: “There is a discussion ongoing about Alexanderplatz and there was also a master plan created for it several years ago which has turned out to be very problematic.
"It has not been carried out for many reasons so the whole discussion about high-rise buildings in Berlin and where they should be put has not been resolved at all.”
The building, which is in a concept stage, also aims to promote communal living and create “a self-determined community encompassing all generations” according to the project outline.
As well as providing communal spaces for food production, the garden city would also offer leisure activities and child care facilities for its residents.
The building, which aims to contribute to the master plan discussion to redesign the eastern city centre of Berlin, has been dubbed die Gurke (the cucumber) by the BZ newspaper.
Preibisz added: “It is not a problem having some organic associations because we want to promote green living and farming. Maybe it’s a carrot, I don’t know.”