A New Conversation with Dennis Pappas: Growing the City Right

Dennis Pappas is a Brooklyn-based landscape architect with over 20 years of experience designing sustainable, community-focused urban spaces. Known for projects like New York City’s first carbon-neutral rooftop garden and the Brooklyn Green Corridor, his work bridges environmental resilience with everyday city life.

Raised in Brooklyn, Dennis developed an early appreciation for the impact of green spaces in dense urban environments. He earned his Bachelor’s degree in Landscape Architecture from Cornell University and a Master’s in Environmental Design from Columbia University, where he deepened his focus on climate adaptation, ecological systems, and public space design.

Throughout his career, Dennis has worked in both the public and private sectors, including with the New York City Department of Parks and Recreation and his current role as Senior Landscape Architect at GreenScape NYC. His work prioritizes native plantings, stormwater management, and inclusive public design.

Dennis is a LEED Accredited Professional and a Certified Green Roof Professional. He is also a member of the New York State Council of Landscape Architects and the Urban Green Council.

Outside of his professional life, Dennis Pappas enjoys kayaking, birdwatching, and photography. He lives in Brooklyn with his partner, Alex, and their two rescue cats, Ash and Willow. His guiding belief remains simple: every green space is a chance to breathe new life into the city.

What’s one thing you wish more people understood about public space?

That it’s not just “extra.” Public space is infrastructure. Just like water lines or roads, green spaces are essential to a functioning city. They aren’t only for leisure—they help with stormwater management, air quality, cooling, and mental health. People often think of parks or tree-lined streets as nice-to-haves, but they are core to a healthy urban ecosystem. I wish more city budgets reflected that reality.

How do you design spaces that feel safe and welcoming to everyone? 

It starts with observation and listening. I spend time in the neighborhood before I draw a single line. I want to see who uses the space and who doesn’t. Is it parents with kids? Seniors? Cyclists passing through? Safety and accessibility are often about visibility—clear sightlines, lighting, pathways that don’t feel hidden or isolated. Welcoming spaces are usually the ones where people can see and be seen, where there’s a rhythm of activity that makes people feel they belong.

What’s the most overlooked tool in your design process? 

Time. I think of time as a design material. How a space changes through the seasons, how vegetation matures, how people’s habits shift over years—it all matters. I sometimes visit sites I designed a decade ago to see how they’ve aged. It’s humbling. What looked good on day one might not hold up after ten summers of heat or unexpected uses. Designing with time in mind makes for more resilient, adaptive spaces.

Do you think cities are doing enough to prepare for climate extremes? 

Not yet. Some cities are making progress, but the pace doesn’t match the urgency. We’re still too reactive. We retrofit after the fact instead of designing for what’s ahead. I’m not just talking about sea level rise. It’s also heat, air pollution, and public health. We need to start treating parks, trees, and green infrastructure as climate tools. They should be part of every emergency plan, not just beautification.

How do you navigate working with government agencies and private developers? 

With patience and clarity. These groups often have very different priorities—budget, timeline, liability—but that doesn’t mean they’re at odds. My job is to translate between them. I frame sustainability as a win for everyone: healthier neighborhoods, higher property values, and long-term cost savings. Sometimes that means showing data, sometimes it's a walk through a successful site. When people see it working, they get on board.

What’s your relationship like with failure? 

Necessary. I’ve had projects where the plant palette didn’t survive, or a space wasn’t used the way we expected. I used to take it personally. Now I see it as part of the feedback loop. Every site is a living thing. People change, weather patterns shift. I’ve learned to leave room for that. The key is building in flexibility—modular designs, native species that can adapt, features that can evolve without a total redesign.

What’s one space in New York City you think has untapped potential? 

Rooftops, without a doubt. Thousands of acres just sitting there—hot, empty, unused. It blows my mind. They could be gardens, community spaces, solar farms. I’ve worked on a few rooftop projects, and every time, people are surprised by how transformative they are. There are zoning and weight limitations, of course, but the potential is enormous. I think the next wave of urban greening will happen above our heads.

How do you bring creativity into a field rooted in science and regulation? 

Creativity comes in through problem-solving. Every site has constraints—budget, soil conditions, zoning. Those limitations actually spark ideas. I like to find the edge of what’s possible and work just inside it. Sometimes creativity is also about storytelling. If I can paint a picture of how a space could feel—what it could give back to a neighborhood—that’s where people get excited. That’s when design moves forward.

What role does emotion play in your work? 

A big one. People connect to places emotionally. It might be a childhood memory of a park or the feeling of shade on a hot day. I try to design with that in mind. A space should invite emotion—calm, joy, curiosity. If you remove that layer, you end up with cold, forgettable spaces. Emotion is the part that sticks.

What’s your hope for how future generations will experience the city? 

I hope they see cities not as places that take from nature, but as places that work with it. I hope they grow up with trees on every street, access to clean air, and parks close to home. And I hope they feel like the city was built with them in mind—that every green space, no matter how small, was a gift left behind by people who cared. That’s the kind of legacy I want to help build.