Rooftop Vegetable Gardener at Rocket Rooftop Garden takes us on a tour!
By Marc Boucher-Colbert 2008
I’m Marc Boucher-Colbert, the rooftop vegetable gardener at Rocket Restaurant at 1111 E. Burnside in Portland, OR. I’d like to take you on a brief tour of Rocket’s garden, but it’s a tour that will not be limited to the mere physical – the beds and crops – but will encompass the vision, history, and philosophy of that garden. After all, doesn’t everything in the outer world have its ongoing conversation with the inner?
And, yes, if you haven’t already guessed, I’m one of those gardener/farmers who came to the profession from a solidly liberal arts background, hence the philosophical musings. I have a B.A. in religious studies and a master’s in education, but my gardener’s training has come from the field, which I came to later in life. Thankfully, I had a latent talent for growing things. For many years I ran Urban Bounty Farm, a city-based CSA farm, and now, in addition to my rooftop duties at Rocket, am Garden Specialist at Franciscan Montessori Earth School in Portland. But I digress – on to the garden!
A Dynamic Place!
Rocket is a constantly changing garden that has evolved considerably in its short one-year lifespan. Up until last month we were still making fundamental changes to the garden as we continued to fill up available roof space with new beds and create suitable paths, but now that we have reached the carrying capacity of the 30’x 70’ roof, I suspect the pace of change will slow somewhat. Currently we have available as growing space two ecoroof sections that were part of the building’s original “green” design (about 150 sq. ft. total), six 3’x 9’ raised beds that are 18” deep, and 39 45” diameter shallow “kiddie” pools (12 square feet each).
Our goal for the garden is to grow food year-round which will provide the chefs with the prime material they need to exercise their creativity. Restaurant staples constitute a large part of what we grow. Leather Storrs, Rocket’s chef/co-owner, gave me this triune mandate to help me plan my crop selection: chives, thyme, and parsley. Apparently that trinity of herbs is like gold in the kitchen, so the garden strives to keep everybody down below happy with ample quantities of such.
The restaurant’s name, Rocket, is a play on two meanings, the cone-nosed spaceship and the Continental name for arugula – rocket or rocquette. Thus, to live up to our name” second meaning, we grow lots of arugula, which forms the basis for the restaurant’s signature rooftop salad. Also inspired by a menu item called Red Greens, we have begun a committed relationship with 10 gorgeous varieties of lettuce, all of whom like to wear the rouge, shall we say. Some, like Speckled Trout Back, exhibit a lovely stippling of red over a green background, while others, like Outredgeous, are so deeply red that if one looked too long, the sheer intensity of red could induce a hypnotic trance. Leather likes a feathery kind of cilantro called Delfino, so we try to keep him in that as well.
Beyond these staples, there are the seasonal changes. We grow mache and endive in the fall, winter and spring, and of course we have tomatoes, eggplant, peppers, summer squash, and cucumbers in the warmer months. Besides the usual garden grammar, there is the whimsical punctuation: a planting of fennel for small, grillable bulbs, some cress thrown in for kicks (literally), the hard-to-find golden-podded peas. Practically anything we grow can get worked into a special, and if any of these occasional items is beloved enough in the kitchen, it may work its way into permanent status. The challenge is and will remain how to leave enough room for the regular offerings while also keeping space available for trailing new crops and varieties.
Farming the Urban Mountaintop
Rooftop gardening presents some fundamental challenges to the terrestrially-minded gardener. Besides the initial investment of energy to haul soil up, there are ongoing and systemic hurdles. There is a lot more wind. It can feel like a pleasant, calm day at street level, and by the time one hits the roof that same weather has tousled your hair and threatened to blow overboard papers, a piece of greenhouse plastic, a garbage can lid – whatever. Wind is very non-discriminatory that way.
To maximize winter production, we cover, or cloche in garden-speak, some of the beds, but our winter storms can deal out gusts of 50 or more miles per hour, so not a small amount of thought needs to go into planning for a bed covering that is at once easy to access, for the chefs’ convenience, but at the same time, tough as nails and not given to flight. In the summer heat, a steady wind is the sucker punch that’ll take down unsuspecting plants every time. Hot, dry air moving over leaves will quickly bleed the entire plant and the surrounding soil of their water.
A roof is a pretty unforgiving environment for growing things, and as a result we’ve had to engineer planters that hold extra water to compensate for the drying conditions (see the illustration of our pools’ water reservoirs in the Oregonian article about Rocket’s garden, linked on City Farmer’s web site.).
Soil is another interesting challenge. On the roof, it’s all about weight. We all know, from hauling a bucket here or there, that soil is heavy, and soil plus water is even heavier (see the table of weights per cubic foot of materials), so don’t even think of taking a bucket of your favorite loam up top. Most conventional roofs are designed to hold only 20 – 30 lbs. per square foot, and even designated ecoroofs take a load that weighs about 50-60 lbs. per square foot. Any rooftop planting medium must be spot-on in terms of weight per square foot, and that usually means using a “soil” that is lean in the good stuff and fluffy with perlite, a popped mineral, or pumice, earth’s aerated magma.
So the twisted logic of the rooftop gardener goes something like this: “I like this soil. This soil is lightweight and therefore good for the roof. Because this soil is lightweight, it lacks nutrients for vigorous plant growth. This soil will not grow veggies well at all. I hate this soil!” Last year’s production in the ecoroof portion of our garden was abysmal (Interestingly enough, this was the soil that we had no control over. It was shipped in by a contractor). Greens pouted and barely grew. Even the tough Mediterranean herbs like oregano were recalcitrant. Thankfully, that same rooftop soil blend has, after a year, apparently become more biologically complex, and our plantings have shown a decided improvement.
The kiddie pools and raised beds were a different story. From the start I used a coconut fiber-based potting blend (made by Black Gold) with spectacular results. We also amend almost every planting with a mix of some or all of the following: kelp meal, glacial rock dust, bone meal, blood, worm castings, or a balanced organic fertilizer (5-5-5, for you garden numerologists), and when necessary, we will water with a dilute organic fertilizer, such as a fish/kelp solution. Our soil depths vary from as little as 3” in our pools to 6”or so in our ecoroof sections to about 18”in our raised beds. I gained the confidence to even think of growing vegetables in as little as 3” of soil by reading the work of Dr. Martin L. Price, whose book Amaranth to Zai Holes – Ideas for Growing Food Under Difficult Conditions should make your eyes bulge and your jaw drop as it did mine. I highly recommend it to any neophyte rooftop gardener.
Why Garden on a Rooftop?
We are assailed these days with talk of our ecological “footprint”. The metaphor helps us visualize our impact on the earth but weakens to the degree that we speak of intangible products like carbon dioxide. How much imprint can a gas leave? Where the metaphor does retain its full vigor is upon any piece of earth that receives a building. A modern structure, by and large, imposes a crushing, concrete footprint on the land, and it’s a foot that never lets up.
The Austrian architect and painter Hundertwasser, who seemed like he was one not to mince words, said something to the effect that by building a structure, one murders the biotic community there (pretty much true, as far as I can tell), and that, therefore, one has a moral obligation to plant the roof and restore what one has killed. As a long-time urban market gardener, I read those words and decided that I needed to think seriously about rooftop agriculture, and that line of thinking, joined with the sympathetic visions of developer Kevin Cavenaugh and chef Leather Storrs, led to Rocket’s rooftop vegetable garden.
Just like an individual building, the city as a whole embeds itself upon the land with a crushing asphalt and concrete print. If we are to restore some sense of community with nature to our urban living (and to survive it seems we must), we have to take on rooftop greening with Hundertwasser’s sense of moral imperative. We need the birds to fly over our cities and look down on green roofs and think, in sustainable design guru William McDonough’s words, “We’re home.”
I look out over the industrial east side of Portland from Rocket’s rooftop and see multitudes of flat roofs – exact outlines of their buildings’ footprints. Each roof is an opportunity to undo a wrong, to create a space that might simultaneously: beautify the city, produce food for its inhabitants, reduce building energy costs, cool the urban island, create habitat for living creatures, and filter and sequester storm water. Hundertwasser might agree with a new architectural maxim: a good head can make up for the errors of a bad foot.
Yes, Rocket’s rooftop garden is about reducing food-miles, and it is about getting the freshest produce the moment when chefs need it, but it is also about closer contact with the natural forces that sustain us, and, in some way, about restoring the life that was cut off when even a “green” building pressed down upon the earth. Thanks to the rooftop garden, the inhabitants of and visitors to Rocket can spend a little less time worrying about their ecological “footprint” and a little more time exploring the possibilities of a building’s verdant, produce-laden “headspace”. Plus, as Alice Waters has reminded us of her work with the Edible Schoolyard: “It is a delicious revolution.”
If you’re interested in rooftop gardening, let’s be in touch.
My business is Urban Agriculture Solutions, LLC
Email is the best way to reach me: Email: email@example.com
Come visit Portland and see the Rocket rooftop!