Chicago’s most famous rooftop garden sits atop City Hall, an 11-story office building in the Loop. First planted in 2000, the City Hall rooftop garden was conceived as a demonstration project - part of the City’s Urban Heat Island Initiative - to test the benefits of green roofs and how they affect temperature and air quality. The garden consists of 20,000 plants of more than 150 species, including shrubs, vines and two trees. The plants were selected for their ability to thrive in the conditions on the roof, which is exposed to the sun and can be windy and arid. Most are prairie plants native to the Chicago region.
Hoya kerrii is in the milkweed family Apocynaceae. Commonly known as Sweetheart Hoya, it is native to southeast Asia. This species, like many other Hoyas, is a vining plant that can grow to over 2 meters tall. Sweetheart Hoya produces thick heart-shaped leaves, which make it popular as a gift for Valentine’s day in some parts of the world. Arguably more attractive are the terminal clusters of star shaped flowers. The flowers give off a sweet fragrance, and produce copious amounts of sweet, amber colored nectar that collects at the tips of the petals.