Flip side of Delhi’s upright gardens

Driving along Nizamuddin flyover, a cluster of plants covering the drabness of concrete seem inviting. Awash in fresh showers, they seem resplendent in their green glory, standing tall in the midst of the monstrous pollution Delhi is infamous for. At the ITO flyover too, potted plants drape the pillars, lending hope to the Green Delhi slogan meticulously painted on some of the city’s walls. 

These are one of the many vertical gardens the Delhi government is on the way to develop, covering flyovers, Metro rail pillars, government buildings, schools, markets, and even historical buildings. 

A vertical garden grows upwards, using a trellis or similar support with an integrated irrigation system. They have been touted as a robust step to fight vehicular pollution in a city that generates 131 tonnes of dust daily, according to figures released by the Union Ministry of Environment and Forest. 

DNA examines the feasibility of the idea and whether it is being implemented in the right spirit.

The concept 

The Delhi government has drafted a charter of places that will be beautified with vertical plants. Bringing on board other government authorities like the Delhi Development Authority, the state Public Works Department, and the three civic bodies, the programme was conceptualised last year. It was executed first on the Delhi Metro pillars on the Dwarka-Noida corridor, among others, after the New Delhi Municipal Council announced that it would make all roundabouts verdant. 

Soon after, North and South Delhi Municipal Corporations (NDMC and SDMC) jumped onto the bandwagon. Both have together allocated Rs 16 crore for beautification of 26 markets, 207 primary schools, 60 roads, five historical structures and two flyovers — all with wall gardens. 

Places of historical importance such as Town Hall, Roshnara Garden, Qudesia Bagh and Ajmal Khan Park, will also be bathed in shades of organic green.

Plans are afoot to plant these gardens with a wide array of flora: wedelia (pila bhangara), ribbon grass, dracaena reflexa (song of India), inerme (sankuppi) and blade grass.

The SDMC has identified six flyovers to be turned green in the first phase of the greening. These are Lajpat Nagar, Andrews Ganj, Sarai Kale Khan, Kalkaji, Nehru Place and Raja Garden.

Taking a cue from Delhi, neighbouring cities of 

Noida and Gurugram have also designed similar steps. For instance, the Noida Authority is setting up vertical gardens on pillars under Metro corridors, elevated roads, flyovers and drains among other places. 

In the Millennium City, the National Highway Authority of India would set up vertical organic gardens at all major flyovers — Rajiv Chowk, Iffco Chowk, Hero Honda Chowk and Signature Chowk.

Vertical garden at Nizamuddin Bridge in Delhi. — Amarjeet Singh/DNA

Absorbents of heat, dust and noise

The gardens are ideal for busy roads that are always toxic with air and noise pollution. An Indian Institute of Technology-Kanpur study claims that plants can trap dust — which contributes 26 per cent of the heat to the dry, relentless Delhi summer. 

Buildings, pillars, rooftops — anything that is concrete — radiates heat, leading to a rise in temperatures. Wrap them in plants, however, and these structures can be coolants to dispel heat, rather than contributors to heat.

According to environmentalists, vertical gardens are an effective measure to combat heat and rising temperature. 

Summer in Delhi is harsh and long. Starting from mid-March and lasting well into the middle of October, the season scorches Delhi and its citizens as the mercury breaches the 46 degrees Celsius mark. 

“Buildings that have green cover on their walls have shown drop in temperature by one to two degrees. Plants absorb heat from the surroundings and cool the surface,” says Dr Kusum Solanky, scholar, the Department of Environmental Studies, Panjab University. 

These gardens improve air quality by trapping dust and smog, regulating the temperature, and filtering out carbon dioxide and curbing the urban heat island effect, which is caused by urban development. 

The plants also act as a natural deterrent to noise pollution by absorbing sound vibrations. 

Already running to seed

Across the city, even as civic agencies are planning to bring more places under the cooling cover of vertical gardens, they have let the existing wall gardens wither away. Besides a handful in Lutyens’ Delhi that were replaced recently or tended to with extra care, most of such gardens are crying for attention already. The leaves have sagged, the flowers wilted, and dust has covered their bodies. 

The NDMC’s vertical garden near Ashoka Hotel is one such neglected garden. It could not withstand the blasting winds of a ruthless summer. The plants have drooped, leaving an unseemly collage of black pots hanging from the wall. The plastic waste left behind broken pots is a cause of worry.

A similar fate was met by the greenery put up on Metro rail pillars at Sikandra Road, Tilak Marg and Mathura Road. They had just been planted in January. 

Unruly citizens have played their part in destroying the gardens, uprooting the plants or simply plucking the pots off the wall and walking away with them in a free-for-all. Though the corporation authorities keep an eye out for mischievous elements, the damage is wreaked routinely. 

The kind of plants used in these gardens also cast a shadow of doubt on the success of these gardens, claim environmental activists.

Chhavi Methi of Chipko Delhi movement calls it a foolhardy idea. Lashing out at the government, she says, “This is not a feasible measure. Watering the plants regularly and shielding them against vandals increases the maintenance cost. It’s been a few weeks and I have already seen pots missing from the pillars of Nizamuddin bridge. These gardens may look pleasing to the eye but one cannot wear green-tinted glasses and ignore the reality.” 

“Is it right to chop down thousands of trees in the name of urbanisation and then erect vertical gardens as redemption?” she questions.

(Left) the trim green vertical garden on Nizamuddin Bridge in the city on Thursday; (right) beautification work at Savitri Cinema Flyover. — Amarjeet Singh/DNA

Shabnam Singh, a horticulturist, calls it a waste of taxpayers’ money. Terming the conceptualisation of the project as well as its execution “dubious”, she says, “I am not convinced that the kind of plantation that is being done in Delhi today is going to have any sustainability whatsoever. When we talk about adding more green cover in Delhi through verti cal gardens, I think ornamentation should be the least of the priorities. It is important to look at longevity of the plants that are grown and sustainability of the floral plants. All this ornamentation which is done under flyovers is a waste of money. It’s incomplete and a contradiction.”

Viable alternatives

Horticulturists vote in favour of climbers for vertical gardens as they would survive and flourish. They dismiss the idea that a few hundred leaves growing out of potted plants which are always susceptible to harm would neutralise the pollution generated by lakhs of vehicles daily. 

Also, the cost of upkeep of these wall gardens is high, since the soil needs to be changed constantly and water irrigation regularly monitored. Singh lists bougainvillea as an excellent low-cost creeper to tackle environmental concerns. 

“Climbers are the hardy boys among plants. They can grow anywhere, do not demand frequent watering and, over time, form a dense and robust growth that can ward off the unkind polluted air of Delhi,” says Dr Ved Pal Singh, former associate professor, Haryana Agricultural University. 

These trailing plants also score high on providing an atmosphere conducive to biodiversity. “In their roots is a throbbing world of hundreds of microorganisms that are vital for soil and nature. They house butterflies and honeybees which aid in pollination,” says Dr Singh.

Dr Singh names a few plants that government could consider for its green project. His suggestions include Thunbergia mysorensis (Indian clock vine), Ipomoea purpurea (purple morning glory), Ipomoea coccinea (red morning glory or redstar), Ipomoea cairica (railroad creeper or mile-a-minute vine), Ipomoea quamoclit (cypress vine), Vernonia grandiflora (a kind of forb, like ironweed), Coccinia grandis (ivy gourd), Thunbergia grandiflora (blue skyflower), Campsis grandiflora (Chinese trumpet vine) and Jasminum humile (yellow jasmine).

Dr Singh cautions, “These climbers won’t instantly grow into thick forests. But give them about a year and they will cling to the walls and pillars of Delhi as lifesavers. Aesthetically, they may not look as pleasing but we need to be wise, not vain, to combat this life-threatening pollution.”

PILLARS AGAINST POLLUTION

STANDING TALL

Vertical garden at Savitri Cenema Flyover in Delhi. — Amarjeet Singh/DNA

APRIL 2017

• Delhi government hit upon the idea of vertical gardens 
   
• Vertical gardening involves growing plants on vertical surfaces of urban structures like flyover columns and buildings with an integrated water irrigation system
   
• Where: Metro rail pillars, flyovers and public buildings to have such gardens

EXECUTING AUTHORITIES

• Delhi Development Authority, Public Works Department and Municipal Corporation, Delhi brought on board for project 

AIM OF THE PROJECT 

• Reduce vehicular pollution, increase green cover. 

SEED MONEY

• Rs 16 crore, amount allocated by North Delhi and South Delhi Municipal Corporations for wall gardens 
   
• Included under vertical gardening are 26 markets, 207 primary schools, 60 roads, five historical structures and two flyovers

KINDS OF PLANT

• A variety of wedelia (pila bhangara), ribbon grass, dracaena reflexa (song of India), inerme (sankuppi) and blade grass to be planted in these spaces 
   
• 6 flyovers shortlisted by SDMC to be turned green in first phase: Lajpat Nagar, Andrews Ganj, Sarai Kale Khan, Kalkaji, Nehru Place and Raja Garden

LOOKING TO SINGAPORE

• Singapore has championed the concept by covering its flyovers’ columns with climbers such as Ficus pumila. Flowering species such as bougainvillea adorn overhead bridges. Along with other methods, the city-state continues to use creepers for its ‘skyrise greening’.

207 
Primary schools will be beautified with the upright gardens in SDMC and NDMC

60 
Roads under the two corporations will be part of the project 

26 
Civic markets in SDMC and NDMC will also see vertical gardening 

CREEPERS THAT ARE MORE ENDURING

A list of vines that greens suggest the government can plant vertically: 

• Thunbergia mysorensis (Indian clock vine)
   
• Ipomoea purpurea (purple morning glory)
   
• Ipomoea coccinea (red morning glory or redstar)
   
• Ipomoea cairica (railroad creeper or mile-a-minute vine)
   
• Ipomoea quamoclit (cypress vine) 
   
• Vernonia grandiflora (a kind of forb, like ironweed)
   
• Coccinia grandis (ivy gourd)
   
• Thunbergia grandiflora (blue skyflower) 
   
• Campsis grandiflora (Chinese trumpet vine)
   
• Jasminum humile (yellow jasmine)
   
• Bignonia unguiculata
   
• Ficus scandens