An exercise in reclaiming ‘unconsidered’ urban space, Bus Roots aims to install gardens atop the city’s buses, creating roving green spaces. Born as a thesis project for interaction designer and artist Castro, the project has reached prototype stage, with a small garden now installed on the roof of Cell Motion’s BioBus, a not-for-profit mobile science education lab which visits schools around the East Coast of the US.

A few weeks after the prototype was launched, Castro spoke to HPHP Central about the challenges and benefits of his project.

What do you see as the key health and social benefits of Bus Roots?

Plants are some of the most efficient organisms I could think of. They are great solar panels, they produce their own food, they don’t produce waste, they don’t pollute, they actually clean and heal the environment around them if they can. They are great heat and sound insulators and become great food for animals and therefore for humans. Plus, they make our surroundings much more lively and attractive.

These are some of the reasons that got me started in thinking that Bus Roots could help the environment. Roofs are typical unused spaces and green roofs in general provide the following benefits to urban environments.

• Diminish air pollution.
• Acoustical insulation.
• Heat insulation.
• By lowering demand for heating and air conditioning use, less carbon dioxide is released from power plants and furnaces.
• Habitat restoration.
• Provide green space for new insect and animal life to live and visit.
• Aesthetic value.
• Conserve energy.
• Storm Water Management, they absorb water that would other wise end up clogging the sewage system.
• Mitigation of Urban Heat Island Effect, they can lower the temperatures and affect the microclimates in the city.
• CO2 sequestration, according to a study at the Michigan State University approximately at 375g Cm2.
• Public education and recreation, they provide ways for people to understand natural life around them and ways to protect it.
• Reclaim real estate for people to enjoy and interact with their community.
• Nomadic agriculture.

You graduated from New York University’s Interactive Telecommunications Program – how did that lead you to what you’re working on now? What are some of the conceptual influences which helped to form the idea of Bus Roots in your mind?

My graduate school, ITP at NYU, provided invaluable support in letting me play with new ideas, experimenting with technologies and materials, meeting new people and allowing me to imagine new perspectives of the world around me. I’m interested in making people interact with their environment, be engaged with it and if possible, encourage people to improve upon on it.

What motivates people to care or not care about each other and whatever surrounds them? If people were passionate about their community, would they be willing to improve it? Would they even dare to change it? I posed myself this challenge: how could I reconnect vibrant urban communities with nature in a practical and playful way? Bus Roots is the solution I proposed.

Many interaction designers begin projects by observing a problem, and considering its solution. What problem does Bus Roots address?

I thought about our relationship with our environment and our reactions to weather. New York City in the 21st Century seems not to know how to handle rain or snow very well. People get angry, sad, and annoyed at rainfall, accidents happen and Twitter feeds fill with catastrophic words.

Plants like the rain. That led to thinking: how had we grown so disconnected from rain? Were cities not designed with rain in mind? So I set out to think of how I could reconnect urbanites to their natural environment and provide a way for them to enjoy rain.

I wanted to make a project that did not have to rely too much on electricity or involve screens that required a dark space. I was looking for a project that was as non- invasive and non-polluting as possible. Something public that could involve the citizens and the spaces they use. It would bring a sense of play and awe to the city. It would be designed to consume the least amount of resources and if possible heal the environment. I came to the conclusion that I wanted a project that could use plants as a medium.

The Bio Bus, home of the first Bus Roots prototype, primarily visits schools — and has been as far as Ohio, Indiana, Connecticut and Washington DC. What has the response been amongst the children and adults who’ve encountered it?

The Bio Bus is an educational science lab that visits schools and learning spaces all year round. In it, the kids learn about biology and the environment. Bio Bus is the first bus to have a green roof; it has the first Bus Roots working prototype.

Through trial and error, the first prototype was designed and constructed. It covers 15 square feet of the roof, weighs 225 lbs and has travelled well so far, for the last four weeks to the Bronx, Long Island, Pennsylvania and Ohio.

Two days after installation, the Bio Bus with Bus Roots on top was invited to Grand Central to participate at the Earth Fair for Earth Day. It was a great opportunity to ask people what they thought about the idea. Both kids and adults were very interested. The more curious ones wanted to touch the plants and see if they were real, while others just passed by assuming they were plastic plants. They were fixed in their believe that buses don’t grow plants.

Observing the BioBus prototype, have there been any unexpected difficulties with your rooftop garden design?

So far the prototype has been very well behaved. We are still in the observation stage; it is a small garden so we will see how it recovers for the spring.

How do you envisage Bus Roots having flow on effects to other aspects of the buses themselves, or the wider public transport system?

I like to think buses with Bus Roots on top would be more attractive and people will want to ride them more or go out to see them. Hopefully that will decrease the amount of single rider cars in the city.

How and when will you determine which of your three plant selections (Extensive Green Roof, Hydroponic System, Green Cloak) will be used for Bus Roots?

I think it will depend on the bus that is using it. At the moment, I’m leaning more for a green cloak. Its lightweight is great to be installed on any bus.

A bus full of people is more efficient than a half full bus. The weight on top of the bus can range from 300 to 2000 lbs, we are still looking into the best lightest option, and once we deploy a full prototype we can look at the efficiency of the bus in real time.

Do you feel the benefits of food production are jeopardized by the increased exposure to pollution the garden would have?

It would be great to grow food on top of the buses. I think there are many ways in which food can be grown and protected from pollution.

How will Bus Roots affect storm water management?

I think it will make a big change once an open-air parking lot is converted from a blanket of white rooftops to a green blanket. The amount of storm water caught can be considerable.

What are some key challenges the Bus Roots project faces?

The biggest challenge has been getting people to believe you can grow plants on buses and that there is one working prototype running around New York city. I expect to tackle this by designing more Bus Roots prototypes and proposing to install it in as many buses as possible.

The plants growing right now are sedum and part of an extensive green roof system. I am looking for lighter weight plants and to find more variety of plants. It requires very little maintenance, the plan is to have the garden be nourished by the rain season, and every once in a while, replenish the nutrients that might be lost.

In the objective of getting the garden on top of MTA buses, I looked at the lowest maintenance garden. However, I would be happy to talk to bus drivers who would want to garden buses.

If a green roof were added to the surface of every one of the 4,500 buses in the MTA [Metropolitan Transport Authority] fleet, 35 acres of green space would be added to the city. That is approximately four times Bryant Park. Doing a rough estimate, it would also mean that 131,250t [of carbon dioxide] would be sequestered by the plants and substrate alone.

Tell us about your plans for the future direction of your work.

I’d like to plant more gardens, experiment with more plants and vehicles. Perhaps, grow some edible plants. I would also like to register carbon levels and storm water management. In other words, I’d like to explore what Nomadic Agriculture means.