A Rooftop Orchard and Food Forest Flourishes on the Javits Centre in New York
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Introduction
As Brooklyn Grange enters its fourteenth season farming vegetables on 7 acres of roofs, we are approaching our one millionth pound of produce grown on rooftop farms in New York City. Naturally, if you know our operations, the vast majority of that food has been a diversity of vegetables through the years.
Picking apples from the rooftop orchard. Photo:Valery Rizzo.
The Javits Center
For our client the Javits Center, we manage The Farm, their 1-acre rooftop farm. It has 18” of soil, a climate-controlled greenhouse, and several perennial flowerscapes. The food that we cultivate and harvest is used by their catering department for events within the building, and excess is donated to a local organization called Rethink, which works to reduce food insecurity in our NYC community. We also manage an especially unique 8,000 sf of soil on their roof at a 42” depth: the Orchard and Food Forest.
Planting of the Orchard Trees in spring of 2021. Photo: Ben Flanner
The Orchard and Food Forest
The Food Forest at the Javits Center began as an orchard of 5-yr old trees–32 apple and 6 pear–installed in the spring of 2021. Apple species include Honeycrisp, Zestar, and Goldrush, among others. Each tree was spaced at about 10ft in-line, mulched in a circle, and white clover was seeded in between to cover the surface. Throughout that season, we predictably observed that the foliage canopies had space to grow until they approached each other, and that there was plenty of photosynthesis potential in the understory. So, we proposed a second phase to the project: phase 2 involved the addition of an understory, turning the project into a biodiverse food forest.
In the spring of 2022 we installed hundreds of perennials, substantially adding to the plant spectrum, food production capability, wildlife habitat potential, and impact of the space. Led by managers Orion Ashmore and Stina Seaberg, Brooklyn Grange planted currants, gooseberries, rhubarb, asparagus, strawberries, american licorice, wild alliums, pawpaw, beach plum, elderberry, yaupon, mountain laurel, cherry laurel, big bluestem, native flowers, and others. We also inoculated our mulched surfaces with hearty winecap mushroom spawn. The plant species were chosen based on being mostly native, all regionally appropriate, and well-adapted disease resistant plants. Most of the plants in the food forest produced food, and some also serve as windblocks along the Western perimeter.
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Winecap mushrooms growing in wood chips. Photo: Ben Flanner.
Today there is a strong diversity of plants, insects, and birds for such a young location, and the space continues to evolve by the month. The apple trees are filling in, producing around 700 lbs per year at this point, and still increasing. The understory is productive too, and filled with surprises. Winecap mushrooms emerge in flushes with the rains and temperatures, while currants, gooseberries, elderberries, serviceberries, and other plants provide a continuous stagger of yields throughout the year.
Biodiversity
We seek a balance, in the spirit of diversity. Regular scoutings ensure that spotted lanternflies, aphids, leafy mildews, leafy blights, and rusts are under control, though likely never eradicated. Wooly aphids appeared in 2022, a first for our 14 years on roofs. We find praying mantises, and have observed impressive insect and bird variety, from wasps, to moths (friend and foe), dragonflies, grasshoppers, lady beetles, katydids, assassin bugs, beetles, ants, hover flies, and spiders. Our partners at the NYC Audubon Society, which has been studying the ecosystem at the Javits Center, remind us that the food forest offers an important habitat for migratory birds to forage and rest during migration. The trees and the understory, unusual features for a green roof, are full of insects, which are food for many of the 65 bird species that have been observed by NYC Audubon. Native bees forage in the understory, Blue Jays come through in fall to feed on apples left in the trees, and sounds from four bat species have been recorded over the forest at night.
Engineering for intensive and extensive green roofs has become more common, and even mandatory in many of our largest cities across the globe. However engineering for a 42” food forest will not be quite as common, as roof loads exceed 250 lbs/sf. But we hope that this special location will serve as inspiration in many other ways - for edible meadows on roofs, at ground level, and for cities to imagine low maintenance, diverse park plantings with meandering walkways. This environmental asset also creates awareness of how important our tree crops are in providing food for insects, birds, and other animals - all the way up and down the food chain.
Platipus deadman anchoring system - also looped around installed concrete curb at base of soil (not visible). Ball was loosened and cut after tree was settled into pit. Photo: Ben Flanner
Irrigation
The food forest is irrigated with drip irrigation, all tied to a large Baseline controller which manages the entire planted roof space through 32 zones. The food forest itself has 10 zones of irrigation. Separate zones isolate the tree rings (2 on each tree), and an array of parallel surface drips spaced 18” apart cover the remainder of the orchard. We rarely run the tree rings - being cautious to avoid oversaturation or root diseases which may be difficult to rid the trees of. The irrigation system was installed and hooked up by RR Irrigation. The soil is a well drained blend with a target of 4-5% organic matter - engineered by Naturcycle and American Hydrotech based on detailed specifications provided by Brooklyn Grange. The purpose of this fairly low organic matter is to reduce settling, as well as to emulate soil characteristics common for most trees. (By contrast, in our vegetable farms, we often look for up to 10% OM). There is a Hydrotech drainage system below the soil. Trees were anchored using a platipus “deadman” system, tied into 3 curbs at each tree in a triangle, which were installed prior to the soil.
Integrated Water Management
One other unique aspect of The Farm at the Javits Center is the massive underground water catchment cistern, which holds 340,000 gallons of stormwater runoff. Numerous drains feed from the roof, into this underground cistern, which holds and then passes the water through a filter as it is pumped back up into our irrigation system on the roof. All of the irrigation of the rooftop space is fed from this cistern. Regular water testing is performed to ensure that the bacteria counts remain below the required threshold.
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Orchard / Food Forest with interplantings, being tended to by Brooklyn Grange crew. Photo: Valery Rizzo.
Maintenance
Maintenance of the Orchard and Food Forest includes an annual heavy winter tree pruning (up to 30% of each tree), annual mulching of the walkways and tree circles, weekly pest and insect scouting, weekly harvesting, light pruning of the understory, and minimal active management beyond that. We continue to stress the value of ecological management, without overly influencing the natural development of the space.
All pest and disease management is organic and almost entirely biological, without any harmful fungicides or pesticides. Over time, we will see how the trees fare through more debilitating mildews, blights, airborne fungi and rusts, and other common apple tree ailments. One advantage is the forests’ perch about 100ft up along the West Side Highway. There is constant fresh air blowing across the East River, and we are optimistic that this breeze will be a long term deterrent to airborne diseases which are a constant threat to organic apples grown in the Northeast.
Conclusion
Brooklyn Grange is proud to provide a unique habitat opportunity for wildlife in this magical urban location, and happy to witness and support the natural evolution of the forest, and to see our trees mature through the years. We hope other property owners in New York City and cities around the world will invest in critical environmental resources like this one, that provide ecological and social benefits to all species with whom they come in contact. We at Brooklyn Grange believe there is tremendous power in urban green space: by reinstating the natural ecosystems that predated the development of our cities, we can build resilience and restore the connection between human society and the natural world.
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Ben Flanner is the CoFounder / CEO of Brooklyn Grange
Visiting New York City? The Javits Center offers weekly tours via their website.
