Stormwater treatment and urban food specialist, Biofilta Pty Ltd designed and installed a pop-up community garden in Davis Street, Kensington in 8 hours this week.
The City of Melbourne has recognised that greening laneways with productive gardens is a great way to build communities and tackle the fact that Melbourne’s food bowl is shrinking at a rapid rate due to urban sprawl.
While it is notionally a good idea to grow food close to where most people live, urban farming has some challenges:
- Much of the inner city land is contaminated which imposes high costs of developing in-ground gardens
- Space is a premium
- Water use can be substantial for vegetable growing in outdoor environments, especially in dry climates
- Many vegetable growing systems lack real soil volume and are prone to drying out quickly during hot weather
- Management of the community garden requires input
Biofilta’s solution to these challenges are to offer a range of vertical and horizontal advanced wicking garden systems that are ultra-water, spatially efficient and easy to install quickly.
The vertical and modular Foodwall system enables a robust community garden to be installed in a day and doubles or triples the available growing space through its stacked arrangement.
The Foodwall is innovative in its ability to provide air to the roots through breathing tubes attached to the soil tray. When the water level is set below the tray, an air loop is created which allows built up gas to escape, temperature to regulate better and enables the soil media to be free draining. The tray also provides columns of soil in contact with the reservoir of water to “wick” the water up to the plants.
With 50 litres of potting mix in each tub, there is a meaningful amount of volume to grow vegetables and add compost to close the nutrient cycle.
Also demonstrated at the Davis Street site are horizontal wicking beds that don’t need the traditional rock and geotextile layers. These planter beds employ the same technology as the Foodwall, only on a larger format. Benefits are ease of installation and ability to wick the entire reserve of water to the plants, no smelly nutrient rich water in the base and no double handling of materials to build the wicking bed.
Each Foodwall contains 22 litres of water for the vegetables to access. Field trials show that a fully planted tub can use up to 3 litres of water per day when temperature is above 30 °C. The Foodwall contains enough water in each tub to last a week between refills. Perfect for the busy gardener or a community garden roster.
Local residents were contacted by the City of Melbourne and invited to participate in the ongoing operation of the community garden. Specialist non-profit organisation Cultivating Community (http://www.cultivatingcommunity.org.au/) based in Melbourne will provide a high level management role and monitor the engagement and output of this garden through weighing produce and tabulating results. The resident driven ownership with an experienced monitor organisation is a great model for sustainable management.
Biofilta have been operating an open air 10m² garden in Bay Street, Port Melbourne for the past 9 months. The actual footprint of the garden is 3.3m² due to the triple stack arrangement. Results of the garden to date is 90kg harvested in 9 months with a range of seasonal vegetables and herbs planted. Average water use is approximately 100 litres of water per kg of produce.
All produce is donated to local charity.
The Bigger Picture
Vertical productive gardens which are soil based and water efficient through wicking, enable solutions to engage the community with meaningful food production while providing a range of social, economic and environmental benefits. Low tech solutions that don’t rely on pumps or fossil fuel derived chemicals are available and can give high quality output to the average gardener. Our goal is to enable cities to become catchments and food bowls. These systems can significantly reduce the cost of vegetable supply and be cost positive within 2 to 3 years depending on the crop grown according to Biofilta’s data gathered from real world gardens.
Roof top gardens and small pocket parks are a key way for cities to become food bowls and the Foodwall provides a means to double or triple the available productive space.
Often sustainability is featured around energy use and lower fuel consumption. We should also talk about food sustainability.
Having the right tools to achieve these goals are now a reality.