EAT UProoftop mushrooms?
Productive rooftops can yield more than just fruits and vegetables. These cultivated spaces can produce unexpected agricultural products such as wool and honey, but what about mushrooms? Most fungal species prefer the shade, and yet there are a few species that blossom in full sun. This morning I launched an experiment to find out if one particular mushroom species has the potential to become a viable, albeit unsuspecting, rooftop crop.
Stropharia rugoso-annulata || (photo by Sue Van Hook)
After gathering miscellaneous green roof fabrics, drainage materials, and soil (known as media) from my office’s materials library, I assembled an ad hoc green roof plot on a balcony outside of my office in Philadelphia. The plot contains approximately 3″ of standard green roof media, and is fully exposed to both sunlight and rain.
New York-based mycologist Sue Van Hook, isolated and cultured a type of edible mushroom called Stropharia rugoso-annulata, and provided me with a bag of spawn with which to inoculate the plot. Generally speaking, spawn is any substrate that contains mycelium, or thread-like “root” cells. The particular spawn that Van Hook provided contained a substrate of wood chips and compost. If the growing conditions are right, this spawn will spread throughout the green roof media and eventually fruit to produce an edible crop of mushrooms.
Test plot 10.12.2011
I spread the spawn on top of the green roof media at a thickness of approximately 1″. There was no need to water, since the air was thick and the forecast called for rain. According to mycology guru Paul Stamets, S. rugoso-annulata often takes 12 weeks to fruit, or produce mushroom bodies. Since my test plot was inoculated in October, fruiting will not occur until next year, if at all. If the crop is successful, then the potential exists to try it on a larger rooftop scale. This experiment could very easily fail, or it could be the start of something big.
rooftop ag for a global audience
In this video clip I discuss the burgeoning field of rooftop agriculture and it’s potential for growth in the U.S. The video was originally filmed by Roofmeadow for the “Green Roofs and Walls of the World Virtual Summit 2011,” which was organized by GreenRoofs.com and held for a global audience this past month.
get up there!
Brentwood Civic Center, Brentwood, CA ||(photo by Lauren Mandel)
You want to grow food on your roof – wonderful. Now how the heck do you get up there?
Rooftop access can be tricky from both an infrastructural and legal perspective. Here are some accumulated observations from my days overseeing green roof construction around the country.
1| Size matters: The roofs on which I’ve worked have ranged in size from 850 to 120,000 square feet (2.75 acres). Small roofs, such as those atop townhouses and small mixed-use buildings, are often accessed by mechanical lifts during construction, and with a head house, roof hatch, or temporary ladder after construction. Large roofs, by contrast, rely upon cranes during construction, and often contain elevators, stairwells, or hatches with secure ladders for permanent rooftop access. In general, large roofs are much more likely to contain the architectural infrastructure that is necessary to access the roof on a regular basis. Most small roofs do not contain adequate infrastructure, and the provision of such is often cost prohibitive.
2| Safety first: When growing food on a roof, structurally secure access is a must. You will need to carry bulky elements such as tubs of compost, hoses, and baskets of vegetables up and down from the roof, and a ladder can be very dangerous for these activities. In order to promote safety, many building codes actually require that certain architectural infrastructure be in place for regular rooftop access. No matter how badly you want to farm your roof, nothing will ruin your weekend like a serious injury; be careful up there!
3| Informing design: Planning for regular roof access during the design of the building can ensure safe and easy vertical circulation. If the roof is intended to be farmed, then consideration should be paid to how and where the roof will be accessed. The rooftop activities may inform what type of access is most suitable, or by contrast, the type of access may inform rooftop activity. Incorporating rooftop access as an afterthought can be extremely expensive, and so it is best to plan ahead for such activities.
trend setter
Friends Center (photo courtesy of Roofmeadow)
Charlie Miller knows green roofs. As the founder of one of the oldest green roof firms in North America, Charlie is a leading force in pioneering the green roof industry in this part of the world. He is fondly regarded within the industry as the “father of green roofs” and the “green roof guru,” and is well respected by practitioners and policymakers alike.
I have the pleasure of working for Charlie at his Philadelphia-based firm, Roofmeadow (formerly Roofscapes), where scientific and philosophical discourse is commonplace. Charlie and I discussed the intricacies of rooftop agriculture last week, and here are some candid excerpts from the interview:
LM | Have you ever written a specification for rooftop agricultural soil?
CM | I have, but I don’t consider myself to be an expert. My opinion is that agriculture is a very diverse activity, and the types of media are going to be very varied depending on the project. The one size fits all perspective for rooftop agriculture is even less likely that the one size for green roofs… Religion and agriculture are both fields where subjective experience trumps science. There are too many variables.
LM | What material do you prefer to use to frame rooftop raised beds?
CM | I would go with Trex or an environmentally friendly, semi-durable material… This isn’t agriculture in the normal sense… You make material choices that are more based on aesthetics and environmental messaging.
LM | What are the most significant barriers to the success of a widespread rooftop agricultural movement in the U.S.?
CM | The same as there is to agriculture everywhere in the United States. The cost of food in the U.S. is the only commodity that has steadily decreased in absolute price for the last 100 years. The price we pay for food today is based on economies of scale and cheap labor. You don’t want an urban agricultural movement to propagate those evils into a city. You want to think that rooftop agriculture can provide a living wage and work on a human scale that provides an intimate relationship between people and their food.
pitch it. pitch it good.
Pitching a manuscript to a publisher is like trying to convince someone that your child is the brightest or your glass of water is the wettest. It’s nerve racking. How can you possibly convince a professional, who reviews manuscripts day in and day out, that yours is special – something different?
Well, step one is writing a pitch letter. For non-fiction manuscripts, this is a lengthy (10-40 page) document that proves that there is a need for your book in the marketplace. The pitch requires clear articulation of your idea, and quantifiable proof that you book will fetch an audience and make money for the publishing house. The pitch includes a snappy description of the book’s premise, the author’s qualifications, a market analysis, and excerpts from the manuscript. The key is to hook the reader with the intro line while effectively capturing the essence of the manuscript.
Step two is mailing the materials and step three is breathing. Yes, in that order. At this juncture, the manuscript and pitch letter are mailed, fingers are crossed, and sleep is finally attainable. Now let’s wait and see how everything unfolds…
fact or fiction
Your average American has never considered growing food on a roof. Truthfully, the idea of “urban rooftop agriculture” sounds a bit far fetched, until you see it in action. These are powerful places. Their power can be seen in watching a child at a rooftop farm pick a cherry tomato for the first time, and instantly gain a new appreciation for her food. Their power can be seen when planting a rooftop farm in an urban food dessert and witnessing the ripple effect of community initiative and healthy eating.
The benefits of urban rooftop agriculture are overwhelming, and yet, building these farms requires overcoming several obstacles. With small pockets of rooftop farms and gardens scattered around the country, and some larger hotbeds, such as Greenpoint, Brooklyn in New York City, how large will this initiative grow?
Is urban rooftop agriculture a fantasy movement, or is it poised to become an integral part of the urban food system?
The rooftop agricultural movement in the U.S. is surely in its fledgling stage, but momentum is rising. Media coverage and the academic buzz highlight the growing interest in this initiative. Growers and young trend setters are taking the risk and building farms above city skylines across the country.
Rachel Carson wrote about the environmental movement in her book “Silent Spring,” before the movement had grown its own two legs on which to stand. This movement is no different. Urban rooftop agriculture will be big. It will be big because cities are expanding, rural farms are succumbing to housing developments, and people need to eat.
tailored rooftop strategies
Some areas of the U.S. are more suited for urban rooftop agriculture than others. As a result, each region of the country requires a carefully sculpted rooftop strategy.
The West can benefit from strategies that emphasise community involvement and efficient water use The region’s high urban population and low amount of precipitation feed into this recommendation, as does the region’s propensity to support community initiatives. It’s worth noting, however, that significant climatic, cultural, and urban development pattern variations exist within the Western region (between the Pacific and Mountain divisions), and so rooftop strategies must be catered accordingly.
A strategy for the Midwest should focus on food production as a teaching tool and production of food for use within buildings. Coupling educational campaigns with food production for use within buildings would not only empower Midwesterners, but would also provide jobs and improve nutrition.
The Northeast can benefit from high-yield commercial strategies that emphasize food localization. Addressing food security and minimizing the transportation of food should be paramount, given the region’s high population density coupled with its high urban population. The incorporation of community-oriented strategies are duly important for the most densely populated cities due to the potential for building community, providing green space, and reconnecting people with their food.
A strategy for the South should emphasize high-value commercial crops and food production for use within buildings. This region’s warm climate and high precipitation levels are ideal for novice and professional growers alike. Additionally, agricultural costs can be kept low in this part of the country given the region’s climate – no greenhouses are needed.
inner snark
In re-crafting and editing “Eat Up,” I catch myself slipping into a mildly snarky tone. Maybe it’s just my inner snark breaching the surface, or maybe it’s because rooftop agriculture is a relatively wild subject matter, that demands a little humor.
The book touches upon technical information, fairly serious subject matter, and cultural critiques, and I find myself inadvertently inserting some snark to lighted the load. Sometimes the snark grows out of control, though, and I have to prune it back with care and precision. An example of an over the top sentence that was removed from the book introduced a chapter on agricultural methodologies (the chapter is called “Seed to Plate”). The sentence initially read: “There are almost as many ways to grow a tomato on a roof as there are to skin a cat.” Admittedly, this sentence grew out of a late night writing session, and it seemed rather brilliant until I read it the next morning and quickly deleted the nonsense.
The introductory sentence to the chapter now reads: “There are many ways to grow a tomato on a roof, but the most effective growing method may be dictated by production goals and building conditions.” Lets save the snark for later.