If other countries have developed commercial roof farms, what’s to stop Australia?
Lots of city folk like the idea of growing food on the roof. The most ambitious aspire to grow something bigger than a veggie patch or community produce garden. Here is an opportunity to make productive use of space, to connect with mother nature in the heart of the city, to provide others with fresh food, to reduce the carbon footprint of food by reducing the miles it travels to reach customers, and to begin to make our cities self-sufficient.
The notion of farming above the city allures. There’s a great, Swiss-Family-Robinsonian satisfaction in the prospect of a commercial rooftop farm.
Is this notion far-fetched? Well, it’s been done successfully in North America.
There are rooftop farms in in Hong Kong and Tokyo.
And Holland has the largest commercial rooftop farm in Europe.
If commercial farms can operate on roofs in other countries, why not in Australia?
But the countries above all have very different climates, economies and labour forces from Australia, not to mention differences in building codes and horticultural standards.
As always with green roofs – and indeed gardens, horticulture and ecology more generally – we can learn much from ventures on other continents and islands. But we also need to address the particularities of our continent, both geographical and political.
Do it on the Roof sees 5 hurdles that anyone currently planning a feasible and sustainable commercial rooftop farm in Melbourne needs to jump.
The first is the business case. The cost of labour in Australia is vastly different from the US, and we are subject to different industrial relations laws. We put this hurdle first because we find many rooftop farm enthusiasts put great effort into leaping the fifth hurdle, only to be crippled by the cost of labour. Our labour costs are high. Who will farm your farm, and how much will you pay them?
Periodically we talk to entrepreneurs who look to leap the hurdle of labour costs by proposing to use the farm work as a point of entry, or return, to the workforce for disadvantaged members of society. This may be a viable scheme. A key point to consider is how you plan to negotiate the highly probable tension between your commercial and social missions. Managing staff is time-consuming, and all the more so if your staff are unreliable or do not have previous training in their line of work. Have you planned how to compete in the market with suppliers whose management costs are lower?
The second hurdle you must leap is to make sure the land you are using is in a zone which allows for use for commercial horticulture. The city buildings on whose roofs you plan to farm are most likely in a commercial zone. Does this zone allow for use of the land for commercial horticulture? Whose support do you need in the council for any alterations you need in the uses allowed to be made?
The third, and in some ways lesser, hurdle is to source the right rooftop for your requirements. For your farm to be profitable, it will need to be of a certain scale. The size of area you require will vary according to what you plan to grow and the climatic conditions on the roof. Note that the climatic conditions on roofs differ from those on the ground. You may need to make assessments of light and wind.
You also need to consider the load-bearing capacity of the roof. What machinery will you require for farming your crops? Which parts of the roof are strong enough for you to use the machinery you need on them, and which parts of the roof do you need to reinforce or design to ensure sufficient structural strength?
Moreover, how will the machines get onto the roof? Is there a lift which can take them, or will you need a crane, and if so, how will it affect your budget? How will your work force access the roof? Is this route accessible at the times of day your farmer and farmhands require?
These logistical questions are not impossible to answer, but they need to be thought through, and their solutions planned, early on. Providing solutions may be costly, so you need to ensure you have budgeted for it.
The fourth hurdle is to plan how you will meet Australia’s horticultural (and, if relevant, agricultural) standards. How will you meet the Horticultural Code of Conduct? How will you provide the level of quality assurance, management of chemical residues, water quality, cleaning and pest control, safety of equipment and materials, and food safety training that the rest of the industry meets? These questions are rarely, if ever, raised in discussions of the viability of commercial rooftop farms in Australia, yet it is crucial to address them.
The fifth hurdle applies to those rooftop farms which are proposed on the rationale that by reducing food miles, they will benefit the environment. If the reason for creating a farm on a city roof is the environmental benefit, then of course you need to check the overall environmental impact of your farm. One area which is often overlooked is the run-off. What will the nutrient load of your run-off be? Where and how will you dispose of it? Will any detrimental affect it has to local waterways be outweighed by other benefits the farm creates for the environment? Does this sort of calculation make sense?
We would love to assist prospective rooftop farmers in implementing their plans for how to jump these hurdles. In the meantime, growing your own native or exotic product on your roof is a great way to use your space – and the more people who become practised at it, the greater the body of knowledge we will build about what works, and how, when it comes to Australian rooftop farming.