originated by: beerbrewingchronicles.com, Miss Bossy Britches, Maluniu, Flickety
A living wall is a vertical arrangement of plants and other organisms that naturally removes toxins and unhealthy contaminants from the air that we breathe. Living walls can be complete ecosystems or simpler configurations of plants that thrive in and help to decontaminate urban environments. Many living walls are indoors, but they can also be outdoors, such as on the exterior walls of buildings.
1 Decide if the living wall is to be set up indoors or out.. An indoor living wall will help to remove toxins from the air. Indoor air can be very high in pollutants and toxins, and given that most people spend the majority of their time indoors, this can impact on your health dramatically. Outdoor living walls can help to improve the exterior environment, but may be primarily used to reduce energy costs during the summer months. Also consider what an exterior living wall will look like during the winter. Indoor living walls can be relatively small and simple, while outdoor walls may be very large and cover a large area of a building. Also, indoor walls will be easy to water and take care of, while outdoor walls will complicated, and perhaps require special building permits and permission from members of the community. A simple exterior living wall may consist of a climbing plant that grows up a wall from the ground. However, it may take a decent amount of time for this type of living wall to grow and become established.
2 Choose the appropriate plants and other organisms. Living walls are primarily composed of plants that absorb and filter out airborne toxins. All plants are able to remove toxins, but some plants are better at filtering out such harmful substances than others. The plants that are especially good at removing toxins include: azalea, bamboo palm, chrysanthemum, spider plant, aloe vera, English ivy, elephant ear philodendron, golden pothos, and peace lily. Different plants can remove different types of toxins, so use a variety of plants. Choose plants that are well adapted to the environment that they will be living in. Account for light intensity (indoor, outdoor, shade, full sun), available water, humidity and temperature. Other organisms that can be used include soil microorganisms and aquatic animals. Soil microorganisms also help to remove toxins, so fertilize the soil with natural, microbe-rich fertilizers. Certain aquatic animals such as fish, amphibians, and mollusks that consume algae and such can help to make a living wall a complete, essentially self-sustaining ecosystem.
3 Build a structure for the living wall. The living wall will be primarily vertical, but can have a bottom area that serves to house additional plants and an aquatic area. A simple structure can consist of a series of shelves. An array of plant containers can also be attached to a wall or hung from the ceiling. A more complicated structure may consist of a vertical wall and a horizontal base. A reinforced layer of growing medium intact with living plants may be hung vertically on a wall that has been waterproofed with plastic sheeting. In this instance, the plants will grow out horizontally from the vertical growing medium. Be sure to align the structure so that every plant will obtain adequate light once situated, and that every plant can be watered properly and easily. This may involve staggering the shelves or containers in some manner, perhaps somewhat horizontally. The vertical wall should be permeable to some extent so that air can pass through it. At the very least, air should be able to freely pass of over or past the wall. Also keep in mind that the growing medium must be somewhat permeable to air (so should not too dense or completely watertight), as the roots of plants require some oxygen. Air should circulate through or over the wall so that the airborne toxins can be absorbed and removed. If making a large or complex wall, an irrigation system (such as a drip irrigation system) should be part of the wall. Walls that consist of a vertical layer of growing medium should be watered with an irrigation system, and water will most likely need to be supplied from the top so that it can trickle down to the bottom. It may be important to use many small plants, and perhaps just mosses, for the vertical wall. The base of the wall may contain larger plants and an aquatic area.
4 Set up an air re-circulating system. If the wall is indoors, the contaminated household air must be circulated over and ideally through the living wall. This will enable the wall to absorb the toxins from the air, as well as help to ensure that the plants remain healthy. If air is actively drawn through the wall, the living wall can be referred to as a biofilter. One box fan can be used to circulate air, or a more complicated system of fans and ducting can be used.
5 Arrange the lighting for the plants. Plants require light, so make sure that they receive enough artificial or natural light. If possible, place the living wall near a window or skylight that receives direct sunlight. Natural light can be supplemented with artificial light. Regular incandescent light bulbs will not provide adequate light for the plants, but essentially any fluorescent light will work. Regular compact fluorescent bulbs can be focused or directed towards the wall to provide high-quality artificial light. There are also other, more specialized grow lights that are used for plants. A timer can be used to turn artificial lighting on and off during the day and night. Be conscientious of the animals that may live in the wall, and provide them with shade and hiding places.
6 Situate the plants in the living wall. The plants may live in soil or a hydroponic medium. If the wall is to be a primarily self-sustaining ecosystem, it should be much easier to use soil as a planting medium. The wall may be partially hydroponic, but be aware that hydroponic chemical plant nutrients may destroy or disrupt the non-hydroponic component of the living wall.
7 Water and fertilize the plants. Different plants have particular water and fertilizer requirements. Over-watering and under-watering can result in unhealthy plants, and perhaps harmful mold growth. Use living, organic fertilizers to introduce beneficial microorganisms to the wall. If animals are living in the wall, be careful not to contaminate their immediate environment and water and food supply with potentially toxic fertilizer. Use fertilizer sparingly, as it can easily kill the plants and other organisms that make up the living wall.