Peter Dowdall: 'Green walls are vital to Cork city's future'

'Wouldn’t it be great if derelict buildings, instead of being covered in graffiti and stickers, were smothered in plants?'

Irish Examiner garden columnist Peter Dowdall at Elizabeth Fort in Cork. Pictures: Howard Crowdy

It is a cacophony of birdsong when you step outside right now. 

It sounds lovely to this mere mortal and I don’t know enough to know if the noises are actually aggressive males marking their territory or if it is more romantic and musical as they serenade the object of their desires. Unfortunately, in our cities, we don’t hear it as much as in suburban and rural areas.

There are peregrine falcons nesting at the moment in one of the towers of Saint Fin Barre’s Cathedral in Cork. These birds normally nest on the edge of cliffs and I wonder if the falcons are trying to be prophetic to let us know that at the moment our urban centres are akin to cliff faces, such is the level of biodiversity and nature in our cities.

I spoke at Elizabeth Fort, at the end of Barrack Street, as part of the Lifelong Learning Festival during the past week. I was talking primarily about living walls and the role that they can play in alleviating flooding caused by excessive rainfall.

These living walls can play a critical role in reducing the water hitting the drainage system and thus reduce the risk of flooding, as is proven in so many cities around the world.

CLIMATE & SUSTAINABILITY HUB

They bring plenty of other benefits, too. They clean our air, removing carbon dioxide and harmful pollutants and in return, they give us fresh oxygen.

It’s a message that needs to be repeated because we forget it all too easily: Plants and trees will give us fresh oxygen for free asking for nothing in return — just to be left alone. They have further benefits in terms of urban climate and cooling buildings but oases of plant life such as these living walls in our towns and cities will play a huge role in enhancing biodiversity.

People like being near nature and the natural world and a town or a city with high levels of urban greening is a more attractive place to live and work. Having access to green spaces and being close to nature is proven to improve our mental and physical health.

Perhaps the best bit, where a city is concerned, is the socioeconomic benefit of urban greening: It leads to less ant-isocial behaviour and more activity in urban areas. 

I posted about this on social media recently and there is such a lot of interest in the subject and a huge appetite for living walls, roof gardens and other urban greening initiatives — the question that I was asked most was whether a living wall can be on a wall with a northerly or shaded aspect. The answer of course is yes, a living wall can feature anywhere, inside or outside, the aspect is what will determine the plant species used.

When choosing plant species to use in living walls we need to think firstly, of course, of the aspect and light level but also the growth rate, for we don’t want them to outgrow the modular system too quickly. Important too to use, if not exclusively, certainly a high proportion of evergreen plants.

I am a huge fan of heucheras, evergreen ferns and evergreen grasses in living walls. Flowers too can be provided by small heathers, little alpine plants such as sea thrifts, and sea campion which will give loads of colour on our walls whilst providing much-needed food for bees in what may otherwise be barren urban areas.

Once we get the bees back into our cities and I mean, primarily, the solitary species more than honeybees, then we begin to see the tapestry take shape once more. 

As the bees feed on the flowers in the living walls and roof gardens, they also pollinate other flowers which then go on to produce seed which then grows into trees and shrubs where birds will nest and other wildlife too will begin to come back once more. Then, mixed with the car horns and hustle and bustle of city life, we will begin to hear the sweet music of birdsong too.

Greening our cities will result in them looking nicer, yes, and more people will want to live and work in them but I am not espousing the virtues of urban landscaping just for these reasons or to doff the cap in some type of greenwashing exercise.

We need to value the importance of the role that plants and the natural world can play in all of our lives. Without them we have no oxygen, we have nothing.

Wouldn’t it be great if our derelict buildings as well as others, instead of being covered in graffiti and stickers, were smothered in plants and living walls? 

All this needs to be paid for, of course, but instead of looking at this as a negative challenge, there is a huge opportunity now for the business and political and educational interests in Cork city to come together and figure out how to do this as the rewards will far outweigh the investment. 

The cost of not doing it is unthinkable.

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