The Field

by Chih-Wei G.V. Chang, ASLA

An Interview with Antoine Nerval on International Practice and Planting Design

“The potential of landscape planting design is often limited by the supply of plant materials, especially when proposing a complex and diverse living system. Such proposals are in many cases considered unrealistic and too expensive…that is why we decided to start from plant collection and plant nursery.”
– Antoine Nerval

Antoine Nerval is an agricultural engineer who designs vertical gardens. He has created living murals and built nurseries around the world, and is currently working on one of the world’s largest botanical gardens in Normandy, France. This interview—conducted by Chih-Wei G.V. Chang, past chair of ASLA’s International Practice Professional Practice Network (PPN), for a research project—sheds light on Antoine’s unconventional practice and approach to landscape architecture and international planting design.

Coming from a French agricultural engineering background, what did you find particularly different working in the field of landscape architecture? Did anything catch your attention practicing alongside landscape architects in the United States?

It has been easy to communicate with landscape architects because I myself also love to draw or ‘graffiti’ on the paper, and the scale of landscape is similar to larger murals. From my point of view, it is a perfect mix between agriculture engineering and art.

I think in the United States, the landscape architecture industry is very mature and professional, but the specialization also leads to the disconnection between plants and design. Working alongside many excellent teams, I was surprised to find little design discussion about planting materials in the early conceptual phase. The plant selection often only got serious at a much later phase, where designers have less control. It is quite a missed opportunity for many talented landscape designers. For me, my first thoughts for any design projects would always be inspired by particular plants or settings, and then the designs evolve around them.

What do you think is the fundamental limitation that keeps planting from having a stronger influence on the design process?

I think the industrialized plant production is, in fact, the biggest barrier for most planting designs. The industry is supposed to help, but end up constraining plant selection by limiting diversity to the scale of economy. In the end, only easy-to-grow, highly-demanded clones are most available. As a creator of living murals, I always want to bring the best nature has to offer, in terms of either the combination of colors, textures, and volumes, or the cohabitation of diverse species in diverse ecosystems. Each set tells a unique story through artistic expression. But how can you have the freedom to elaborate the design you dream of when the plant palette is so limited?

On another note, the mass production of plants can be awfully unsustainable. Industrialized plants are grown in energy-demanding greenhouses, with 24/7 grow-lights and use of chemicals. They might look good at the time of sale, but when plants are shocked by the outside environment, they usually die and need to be replaced. The lack of genetic diversity makes cloned plants vulnerable and dispensable, and also weakens our world’s vitality and richness.

What is your response to this systematic challenge of the planting supply chain? Tell us about how you reshape your practice.

My fiancée and I always had a dream of building a nursery that grows diverse and healthy plants to supply any like-minded landscape designers. It might sound unrealistic in the beginning, but we followed our instincts and thought that we can always start from ourselves. At first, we dived into plant preparation and grew the plants we proposed. Over time, the “plant palette” we fostered in return also fuels our design ideas and strengthens our design credibility. When the number of plants can no longer satisfy our proposals, we ventured further to collect rare species to enrich our palette. Today we have two greenhouse nurseries with a total of approximately 20,000 square meters and 2,000 different species of plants. Hundreds of thousands of plants are prepared and coordinated with the dynamic design process for our vertical gardens.

In addition, we believe that the landscape industry should be environmentally positive, instead of “greenwashing.” Therefore, we avoid unnecessary chemicals, refuse to rely on cloning, and prefer to grow plants from seeds. This practice can also train the plants to adapt and thrive, either in less heated or less cooled environments.

Not many designers go as far as to find their own plants. Can you tell us more about your plant hunting, and how did you start from scratch?

For us, it is a responsible way to “learn” before we “invite” a plant. As a designer being in a plant’s habitat, he or she truly understands what that particular plant needs. Plant species communicate and express so directly on their nature and identities. For example, when we created the green living wall project for the Australian embassy in Beijing and the Australian company Lendlease’s headquarters in Shanghai, there is no material better than some of the most beautiful ferns in the world, native to Australia: Dicksonia antarctica, Cyathea australis, Cyathea medullaris, Cyathea cooperi, and Microsorum pustulatum (also called the ‘Kangaroo’ fern). All of them are happily growing on the walls!

But allow me to clarify: we didn’t just go out there and smuggle plants. Plant transportation is usually regulated by the Ministry of Agriculture in each country, as well as by a global organization called CITES [the Convention on International Trade in Endangered Species of Wild Fauna and Flora]. Sufficient preparation and coordination is critical, as the damage from invasive species is a huge concern.

This is really interesting. It reminded me of the era where plant hunters launched grand expeditions for scientific research, as well as for prestigious collections at the time.

Yes, it echoes great adventures and stories out there! Let’s not forget that many of the common landscape plants we use today were collected hundreds of years ago by these pioneers and were adopted through cultivation. For example, did you know that one of the most common green indoor plants found in homes around the world, the Epipremnum aureum, is native to French Polynesia, small islands in the Pacific? It is hard to believe how remote a place it came from.

When you own a garden, you are practically a plant collector. Chances are, your plants came from different continents, and represent different living strategies of their ecosystems. And to honor that, providing an optimized environmental setting is a must—and not just to keep the specimen alive. We want them to thrive at their best shapes, and become an art piece in the way they are complemented by other plants. It takes deep observation and long articulation to imagine and construct. And after construction, it still requires significant tending and monitoring.

Continuously taking care of these plants is another key. How do you maintain these rare gardens you create?

Taking care of our gardens is such a pleasure! Personally, I find it a bit similar to meditation or contemplation, and I love being responsible for it. Our office always asks for an extended maintenance period for our creations. Since we grow our plants, we know their life-cycle much better and therefore can maintain and tend them with deeper understanding.

“Maintenance” is not really a good word for what we do. It sounds like keeping something as it is. But for living materials, the beauty lies in how they grow, regenerate, and continue to render their stunning characters. One of our first projects, for Clariant, is living proof of this ability to thrive. Ten years after installation, the “green wall” has evolved from a rather monotonic surface in the beginning, to an unapologetically expressive mural. A green mural has a spirit, and we strive to let it speak.

It sounds like a humbling experience to involve plant life-cycle from the very beginning till the end in the design. What is the ideal time-frame to plan for?

Indeed it is a privilege and a blessing, that we have the chance to work with plants throughout the process. The difficulties obviously vary project by project, but in general, I would suggest the following framework:

1. Intensive dialogue with the owner and project team early in the planning phase.
2. Plan for the plant preparation period, depending on species, from three months to three years. This period can be optimized when parallel with the design phase.
3. Secure right timing and enough construction time for plant installation on site. Planting is usually the last step of construction sequences, and it is often rushed and not done properly.
4. After the plant installation, there should be at least one year of intensive care for plant establishment, followed by three years of monitoring until a balance is reached.

Another key is to foster stewardship of the owners and users. At the end of the day, the gardens belong to the community who live, work, and cultivate them. It should be a joyful responsibility to take care of the plants, and grow the mural together with them.

Is there anything else you’d like to share with ASLA members?

I would love to recommend a book that I recently read: Gardens: An Essay on the Human Condition by Robert Pogue Harrison. The author examines gardens of all kinds: real and mythical, common and majestic, past and contemporary. Through history, religion, art, philosophy, and poetry, Harrison views gardens as both a model and a location for the laborious “self-cultivation and self-improvement that are essential to serenity and enlightenment.” This book also includes my latest favorite poem from Patrick Lane’s What the Stones Remember: A Life Rediscovered. I think they would provide fresh perspectives and inspiration for my fellow landscape architects.

Antoine Nerval is currently designing a 20,000-square-meter indoor tropical scenography for an upcoming botanical garden in Normandy, France. For more works from Antoine Nerval and his partner Bei Mingzhu, visit mingzhunerval.com.

Chih-Wei G.V. Chang is Project Director of Gravity Praxis from the University of Cologne and a past chair of the ASLA International Practice Professional Practice Network (PPN).