A vertical garden at the heartland

I was at Jurong West Street 52 and saw this garden.

Vertical Garden at Heartland?

Plants were growing out from the windows. It seemed that the owner had extended his flat out to the corridor and put grilles on the railings. I'm not sure whether the owner has purchased the common areas from HDB or not. The plants were draping down from the window grilles. I was wondering how the interior looks like.