Up against the wall: How vertical gardens are cooling Dhaka’s homes

When Lutfun Nahar, a Dhaka-based school teacher, started gardening on her balcony, all she had was a broken bucket and some kitchen waste mixed with soil. One day, a delicate tomato seedling poked its head out from beneath the bucket, and the 45-year-old screamed with delight like a child.

For the past three years, Nahar's balconies have transformed into modern-day hanging gardens filled with trails of Kunjolota, pothos, bougainvillaea, and monstera, among other plants.

"I started with cuttings from my neighbours, relatives, and friends, propagated them in jars, and planted them in broken ceramics. From there, I built connections with local nursery owners who now call me whenever they get a new variety of vines or plants," Nahar said.

Dhaka, home to roughly 3.66 crore people packed into about 306 square kilometres, is one of the most densely populated cities in the world. In a city where buildings rise so close together that neighbours can practically shake hands across balconies, the idea of a garden can feel almost satirical.

The Bangladesh Institute of Planners (BIP) estimates that Dhaka has less than 8% green coverage, far below the WHO-recommended minimum of nine square metres of green space per person. The situation has pushed residents — especially the growing urban middle class — to rethink what greenery means and where it can exist.

The answer they have found is vertical gardening. Once the preserve of expensive hotels and corporate office lobbies, vertical gardens and green walls are slowly appearing on apartment balconies, rooftops, boundary walls, and even in living room corners across the city.

Common indoor plants, such as pothos, ferns, peace lilies, philodendrons, calatheas, and anthuriums, are good for creating vertical gardens.

Growing demand for an old concept

Simply put, vertical gardening is the practice of growing plants on a vertical surface rather than horizontally on the ground. This can mean a trellis of climbing vines on a wall, a series of pots arranged on stacked shelves, pocket planters sewn from jute or fabric and hung from railings, or elaborate modular systems of interlocking panels irrigated by a drip network.

The concept has existed in traditional forms for centuries — think of the vine-covered boundary walls of Old Dhaka's heritage homes — but its modern, intentional revival is a response to urban compression.

In recent years, nurseries in Mirpur, Agargaon, and the plant markets along Khamarbari Road have reported a visible uptick in demand for compact and climbing plants: golden pothos, spider plants, areca palms, heartleaf philodendrons, and herbs such as pudina and dhonia that serve as both ingredients and greenery.

Social media groups dedicated to Bangladeshi gardening enthusiasts — some with tens of thousands of members — overflow with photographs of repurposed plastic bottles, bamboo grids, and upcycled wooden pallets transformed into planting walls.

"Demand has increased significantly compared to before, especially since the pandemic, as people have started to realise the importance of greenery at home," noted Md Giasuddin Akash, Managing Director of Baganbari Landscaping Ltd.

Almost every home in Dhaka, he said, is suitable for vertical gardening in some form — though the design and method may vary.

A dense layer of foliage also acts as a buffer against road noise, which in Dhaka is a major concern.

"Lightweight modular panels are ideal for apartment balconies or indoor walls, while rooftops or boundary walls of houses can accommodate larger and heavier installations. The main challenges are sunlight and water management. However, with today's technology, these issues can be addressed quite easily through drip irrigation systems and shade-tolerant plants," he explained.

An expensive investment?

Akash identified a lack of information as one of the major barriers to the practice.

"Many people do not know that it is possible to start a small vertical garden with as little as Tk500 per month," he said.

"An old plastic bottle or a wooden pallet can be turned into a wall pocket at virtually no cost. Buying three money plants or pothos would cost around Tk200. A simple self-watering system can be made with a small drip bottle or a piece of string for about Tk50. Soil and fertiliser together would cost another Tk100. The remaining Tk150 can be kept in reserve to add a new plant the following month," he explained.

"Within six months, an entire wall of your balcony could turn green."

Common indoor plants, such as money plants or pothos are available for Tk50 to Tk150. In the mid-range category, ferns, peace lilies, spider plants, peperomias, and snake plants typically cost between Tk200 and Tk600. Larger and more exotic species such as philodendrons, calatheas, anthuriums, and monsteras can range from Tk800 to Tk5,000.

"As for complete vertical garden installations, the cost usually ranges from Tk1,200 to Tk4,000 per square foot, depending on the quality and design," he noted.

The appeal of green walls

The appeal of vertical gardens is not purely aesthetic, though their aesthetic value is considerable. A well-designed green wall on a west-facing exterior can reduce the surface temperature of that wall by several degrees — a meaningful benefit in a city where April and May temperatures regularly climb beyond 38°C and electricity bills spike because of air-conditioner use.

Plants transpire, releasing moisture that cools the immediate microclimate. A dense layer of foliage also acts as a buffer against road noise, which in Dhaka is far from a trivial concern.

Indoors, plant walls improve air quality by absorbing carbon dioxide and certain volatile organic compounds, though the scale of the benefit depends on the number and species of plants. NASA's Clean Air Study identified several species now popular in Bangladesh — pothos, peace lily, and snake plant — as particularly effective at filtering indoor pollutants.

There is also a psychological dimension. Multiple studies in environmental psychology have found that access to greenery, even in small doses, reduces stress and improves mood. In a city that offers its residents very little breathing space, a wall of living green is not a luxury; it is a form of self-preservation.

A slow but steady shift

A shift in practice is clearly visible. Architects and interior designers working in Dhaka are increasingly incorporating vertical greenery into their proposals.

A handful of residential buildings in Bashundhara and Uttara have incorporated green walls into their common areas and lobbies as a selling point. Rooftop farming — a related but distinct practice — has already demonstrated that Dhaka residents are willing to invest time and effort into reclaiming space for nature.

The vertical garden movement in Dhaka is not a revolution, at least not yet. For now, it is a collection of individual acts — a retired schoolteacher growing bitter gourds up a bamboo pole on her balcony railing, a young software engineer training a monstera across a bedroom wall, or a family of four whose kitchen window ledge is barely visible beneath hanging herb planters. Each is a small negotiation with the city: a refusal to accept that, because space is scarce, greenery must be absent.

However, many residents want to start vertical gardening but do not know where to begin. For them, Akash suggests keeping the first step simple.

"Start with two or three hanging plants in the part of your home that receives the most light. Choose easy-to-maintain plants such as money plants or spider plants that can survive in both sunlight and shade. Once you gain confidence, gradually add panels or trellises. Gardening is a habit, not a project — even five minutes a day is enough," he concluded.