The organic rooftop urban farm at the WOHA Office demonstrates how skyrise greenery can not only be an attractive sustainable contribution to the city, but also productive!
In 2015 we transformed the rooftop of our office into a nearly 200 sqm lush urban farm, featuring over 100 species of edible plants- including herbs, vegetables, leafy greens, fruiting trees and creeping vines. Plants are grown in box planters, loose pots, vines on trellises, and within an aquaponics system- all of which are watered via auto-irrigation fed from rainwater.
The front area of the farm is a productive showcase farm garden with casual seating amongst edible greenery, shade vines and ponds with edible tilapia fish and consumable water plants.
One of the highlights of the farm is an aquaponics system, which consists of a tilapia fish pond and a sloped planter bed. Water containing fish waste is pumped from the pond into the sloped planter bed, where it is cleaned and filtered by the plants and vegetables, and returned by gravity to the fish pond through custom stainless steel water spouts.
At the back, the installation of a new efficient air-conditioning system has freed up ample area for farming activities and experiments with different types of urban farming systems. A workstation is also provided for planting and propagation of plants and sprouting of seeds.
Organic waste produced by the office is collected and composted in both compost aerating tumblers and a worm composting system. Fresh compost and worm castings are then used to return nutrients to the soil, organically supplementing plant growth and creating a complete biological cycle.
Rainwater from tropical monsoon downpours is collected into water tanks, which are used to supply water to the irrigation systems on the rooftop. The rainwater system is designed to supply the entire irrigation requirement of the rooftop farm, even through drought periods of up to two weeks.
Above the farm area at an inaccessible roof area, a 120 sqm photovoltaic (PV) array which supplies around 7% of the office power consumption.
We have been able to grow a wide variety of produce including herbs, vegetables and leafy greens, productive trees and many types of climbing plants. The plant selection is tailored to the humid season-less tropical climate.
Since the construction of this rooftop garden, urban farming has gained popularity in Singapore and throughout the world. It has been a very interesting hands-on research project, and has gotten me very excited about the great potential for food production in cities for the future!
Images by Jonathan Choe
