The purifying power of having the garden on the façade

Vertical gardens, those green structures that cover large walls of emblematic buildings in the city, are more fashionable than ever. They have benefits for those who own them and for the environment in which they are found. They oxygenate and green the environment. Why don’t they proliferate more? What is needed so that a high percentage of the walls of the cities, so avid for nature, do not have that protective mantle?

To answer this question, you must first understand what exactly a vertical garden is. Because although anyone can imagine it, the climbing plants that we see in some buildings (especially houses) may not actually be a vertical garden.

Andrea G. Padin, architect and landscaper at La Habitacion Verde (architecture studio specializing in terraces and gardens responsible for installations such as the interior garden of Hospital Puerta de América), explains that a vertical garden is a surface of plants that “grows on a base with a very specific technology. This base reduces to a minimum, and even almost eliminates, the volume and weight of the substrate on which the plants grow, which allows landscaping slopes of up to 90 degrees above the ground we walk on.

Before the development of this technology, these surfaces could only be covered with climbing plants or with integrated planters that had a similar effect. However, you have to be careful with climbers, as they could damage the walls of the building.

more than aesthetic

Vertical gardens can be both indoors and outdoors in the open air. In addition to being an aesthetic resource that can improve the urban landscape (something that, according to this landscaper, improves the perception of the inhabitants of their urban environment, since the presence of plants helps us feel good) its benefits are multiple and varied.

On the one hand, they open up new possibilities to increase green areas in urban areas, explains Padín, who also talks about how this reduces the ‘heat island’ effect of large cities and, at the same time, reduces the interior temperature of a building in summer, keeping it warm in winter, with the consequent savings in cooling.

According to the data provided by this architect, a 4-storey building with a vertical garden facade filters 40 tons of harmful gases and 15 kg of heavy metals per year.

Care before the show

Andrea G. Padín also assures that this type of garden is an advertising claim, which ends up leading to an increase in visits to the areas where they are installed. Something that, however, also has its cross.

“The boom that took place a few years ago with this type of garden, at the height of the architecture of the show, did them a disservice, because on many occasions installations were made that were not well planned and that failed,” says this expert, who considers that, although its aesthetic capacity is very high, «when this type of garden is not well cared for, the truth is that it also becomes very evident. Failed vertical gardens also get a lot of attention.”

I can have one?

Vertical gardens also have the property of trapping dust and generating oxygen, which can improve our quality of life in a short space.

But we must be aware that we are talking about facilities that have a high cost and maintenance. “In general, these actions have been carried out on very high vertical walls, which greatly increases the cost of maintenance as it is necessary to use very specific auxiliary means such as cranes”, details the architect.

However, he stresses that when the height is not excessive, the result and maintenance cost ratio is “more than reasonable”. “In small vertical gardens it’s important to think about more controlled heights,” she says.

If we wanted to have a vertical garden, Padín recommends being clear that when designing it, it must respond to certain objectives and a project. “Many times it is used as a claim or whim without assessing whether the design solution is suitable for the space, the client and the subsequent maintenance circumstances,” he insists, adding that aspects such as the orientation of the wall and the selection of species is ” key for the vertical garden to be successful and evolve in all its splendor».

source of biodiversity

The good news is that a vertical garden supports a wide variety of plants, so the ornamental result is “spectacular in a minimum space”. In fact, this type of garden at ground level takes up almost no space. “Between the structure and the plant part we can be talking about 30-40 cm, so at the occupation level it is more efficient than putting a standard planter,” says Padín.

To the benefits of vertical gardens, we must add that they can be the habitat of birds and insects, which also guarantees the maintenance of biodiversity.

In addition, it banishes the fear of having more insects inside the building due to having a vertical garden. «The only precaution we must take is to control the irrigation system, since vertical gardens are more delicate. Having almost no substrate, they depend completely on the food they receive with irrigation,” he explains, adding that, otherwise, there are no differences between having a soil garden or a vertical garden at other levels, such as an increase in allergies or the presence of insects.

The results of putting one of these installations will be seen relatively soon. According to the architect’s calculations, between 4 and 6 months is the time it takes for a garden to be completely finished and with the plants in bloom. In addition, it is compatible with lighting systems or ornamental fountains and, as he recalls, “improves environmental conditions, purifying the air and reducing insolation, so it works as a natural air conditioning system if it is installed properly.”