That traffic circle island is maybe 50 feet across, but there's just enough in the way of plants and such that drivers are unlikely to notice anything other than the road. And since Ontario drivers have no clue how to drive on a round-about, only the truly brain-dead would risk looking elsewhere.

BTW: the Experimental Farm is a working farm surrounded by urban Ottawa where scientists perform agricultural research. And loony citizens frollic in the shrubberies. :o