Green Walls and Vertical Gardens
Buildings that Breath, Green Walls, Vertical Gardens or Podium Landscapes Whatever you want to call them, these types of landscape elements are an important aspect of modern Architecture and Landscape Architecture.
They are making a significant difference to the living and working spaces where we spend so much time.
These elements have some notable benefits when incorporated into the urban fabric. There are important considerations that must be addressed both during construction and for the lifetime of the building including additional maintenance requirements.
Gardens in the Sky
Essentially, planning for ‘green space’ for each individual apartment throughout each level of a building takes a reasonable amount of planning.
However, through clever design, incorporating the interior and exterior space provides huge opportunities to maximize living spaces. Utilizing every part of the minimum floor allowed within the building footprint constraints is desirable.
In addition to this, ‘aspect’ plays a critical part of planning these areas as each side of the building receives different climatic conditions.
Careful consideration of light and numerous other conditions is required to ensure the success and longevity of any particular species.
Green walls are simple solutions to provide vertical green elements without taking up significant space. There are now countless products available and methods to installing a green wall.
Two main types of green walls that are becoming more and more popular are;
- those that are really facades of vegetation growing up a wall, trellis or wires
- those where plants are directly planted into a vertical structure that includes a growing media.
All forms of green walls require on-going long term maintenance. The amount of maintenance expected can be less than you think.
The most cost effective method to achieve a ‘vertical green effect’ is to train a suitable climber to an existing wall or fence.
An effective example is the ‘Creeping Fig’ (FICUS pumila) pictured growing directly on a concrete wall.
It will work just as effectively on timber, brick or stone, and will provide almost 100% cover in a suitable position.
However, most climbers will require some kind of trellis system and training to suitably cover a wall. Particularly many of the flowering species.
Another example of flowering species trained to a wire cable system. A fairly dense cover has been achieved with this species rather quickly due to the sunny position.
Using several climbing species can provide more colour and texture variation, but could look messy if not controlled.
One advantage of a utilising a trellis is that it is not restricted to a flat plane. Trellises can be designed to include varying shapes and angles, and can be designed to include something 3-dimensional as demonstrated below.
The many design possibilities can provide significant impact, particularly when dealing with a large monotonous building facade.
The challenge with climbers is to provide for their longevity, which is essential to the success of the green wall. Climbers will require access to deep soil at ground level or planters of a suitable size.
These factors need to be considered early in the design process to ensure required loads are factored into the engineering of structures.
Maintenance requirements depend on the desired effect, but providing access to all areas is a good idea so that maintenance can be carried out if and when required.
The main advantage of this option is that is can be installed nearly anywhere, particularly when a space is not purpose built, and the weight of significant podium planters is not an option structurally.
Installation of a living wall of any significant size will require a survey of the structural features of a building or wall to ensure safety. Permits may also be required in some situations.
A substantial green wall made up of a variety of plants can provide the instant effect of a lush vegetated wall.
There are a number of suppliers around that specialize in installing these types of green walls. This example in King George Square provides a rich variety of colour, texture and form to what otherwise could be a very dull space.
Something like this may cost up to $2500/m2 to install, depending on the overall size and complexity of the project.
Hydroponic systems contain no soil so rely on the nutrients being added to irrigation water. Some sources report that these systems may be environmentally damaging as these nutrients may be released with waste water and end up in the sewer system.
The fact that these systems are made up of a few layers of felt means they can only support small plants. If plants get too big, these areas of the wall will need to be replaced otherwise large plants can rip the matting apart. Because of this, a hydroponic setup is more suitable for smaller areas.
This type of system is ideal for using epiphytic plants. Epiphytes derive nutrients and water from the air and water, and are therefore an ideal option for a wall. The use of epiphytes as green walls is one way easy way to achieve a striking result, as long as site conditions are suitable for the plant selection.
Other systems are effectively a large flat bag of planting medium in a supporting cage structure. This is managed much easier with small vertical gardens. A large area is normally broken up into multiple panels for ease of maintenance.
Module systems are made up of plastic interconnecting modules containing planting mix. These also require the mix to be replaced on a regular basis depending on position. The benefit is that modules can be replaced individually as required, the volume of growing media allows for more significant planting. These systems are generally the most expensive to install.
The cost associated with any type of vertical garden depends on many factors such as location, plant species, height, framing, lighting and irrigation requirements.
A professional installer will need to know specific details about the project to provide an accurate quote.
Finally . . .
All forms of green walls require on-going long term maintenance. Not only the installation cost, but accessibility, practicality and the desired outcome should be considered thoroughly.
Does the space warrant the expense of an instantly stunning feature or will ‘greening up’ the area be adequate?
Is ease of maintenance a priority or are you happy to pay for specialist maintenance personnel where required?
* Images by Citicene. Designs by others.