From the verdant walls of the car park at Dbayyeh's Le Mall to the lush plant life sprouting on Beirut Souks' rooftop restaurant The Garden, green walls are springing up all over Lebanon, mirroring global trends toward eco-friendly, sustainable architecture.

Green walls, or vertical gardens, have increasingly been integrated into public and private buildings around the world over the past decade. Their aesthetic appeal -- particularly in a concrete jungle like Beirut -- is matched by more practical benefits. As well as helping to counter pollution, they help insulate interiors from heat and cold and require less water than traditional gardens.

Many of Lebanon's vertical gardens are the work of local firm Green Studios. The partners in the company, which was founded in 2009, have been working on creating green walls using hydroponic technology -- growing plants using mineral nutrient solutions and water, without soil -- since the early 2000s.

"The industry is very young. It's something like 10 to 15 years old," explains Jamil Corbani, CEO of Green Studios. "It started for aesthetic purposes, but now everyone is exploring the insulation advantages to reduce global warming. In modern cities, you have a lot of heat coming from cars, pollution coming from reflection of buildings, glass, steel and asphalt. ... This -- among other solutions -- is of benefit.

"There are five or six companies ... that are proposing solutions using hydroponics for vertical plantation," he adds. "We are one of them, but the difference is we have a technology that was engineered from the very beginning to sustain itself in super-hot weather. This technology has the advantage of retaining a lot of water and sustaining perfect equilibrium [in temperatures of] 50 or 55 degrees."

Green Studios' gardens are tailored to survive Beirut's challenging environment in other ways as well.

"In Beirut, you have a lot of electricity cuts and water cuts," Corbani points out. "We started from the very beginning developing a smart system to adapt to such shortages. We ended up with a smart system that can change irrigation patterns and change the settings of the system depending on the outside weather and the outside conditions.

"It transmits an alarm signal via SMS or email to the client and to ourselves if there is an electricity cut, and for some projects we have back-up batteries to launch the pumps and continue irrigating the system.

"Our system can also automatically emit an alarm signal in case there is a problem with the water supply or with the water having a dangerous level of salinity or acidity."

The vertical gardens are designed to be eco-friendly, and many of the larger projects use wastewater from their host building to sustain the plant life, recycling the runoff from showers and sinks -- known as graywater -- rather than using freshwater.

"If it's a very small project, maybe the graywater is not collected," Corbani explains, "but if from the very beginning you're planning a building, a living space or a corporate office, it's very easy to use the graywater. ... [Even when] you're not recycling the water, the consumption is something like three times less than any other garden."

Green Studios is currently the only company in the region that has developed the technology to implement vertical gardens outdoors, away from a controlled climate, Corbani says. The firm has already set up green walls in Lebanon and Egypt and is working on projects in Dubai, France and the U.S.

Its technology appeals to a global market, Corbani says, thanks to competitive prices and links with the Lebanese diaspora.

The gardens are created using layered textiles, a sponge or "skin," which retains water and allows plants to take root. The team has tested 145 varieties of plants and are able to recommend a suitable selection for each project.

The idea began, however, as an agricultural experiment.

"We were working on vertical applications for strawberry plantations and lettuce production in water -- hydroponics," Corbani recalls. "That was pure agricultural research, but then in 2009, I assembled the team and we decided to invest what little capital we have in the same technology, but applied on landscape -- aesthetics.

"Now, with our new technology, we're capable of assembling vertical gardens meant to produce edibles: basil, strawberries, tomatoes, everything. So now we're starting applications in agriculture again -- urban farms. Farms on your roof, vertical farms on car parks, buildings, so people can collect their own crops in their neighborhood -- this is what we're working on now."

(c)2014 The Daily Star (Beirut, Lebanon)