A section of Japanese garden

It was, as he described it, on ledge sticking out from the pedestrian bridge at Redfern station: years of southerlies blowing dust from Botany Bay had left enough soil for a section of a Japanese garden, with bright, lush moss and a Bonsai tree with yellow flowers, but it is rare that anyone looks at it because going up those stairs it's hard not to step on the heels of the person in front.