Using Green Walls and Roofs
Making your house more beautiful by creating lovely green walls and roofs
Green façades involve using more traditional methods of growing plants and adapting these to suit. For instance, they can include climbing plants growing up the face of a wall from ground level or from planter boxes located on balconies, trailing plants hanging over the face of a wall from containers on the roof or a balcony, espaliered
trees trained across a wall, or the use of containers such as barrels and urns used to frame doorways.
Plants may be grown in the ground at the base of walls or in containers. Containers can be secured to walls, located on window ledges, balconies or roofs - wherever it is feasible.
Options for Creating Green Façades
Some ways of creating a green façade are as follows:
Trellis is used to support climbing plants. It is traditionally made from wood, although metal trellis can be acquired along with some plastic versions. Trellis is a latticework which can be secured to walls and other structures where it provides a framework for plants to grow and be trained. Trellis panels can also be framed and secured to the tops of walls enabling garden walls to become taller and allowing for climbing plants and vines to be trained vertically.
An alternative to trellis is to use a series of galvanised wires fixed to the wall's surface and to use these to attach and train climbing and trailing plants. Typically, wires are secured in horizontal rows about 30cm apart using vine eyes spaced at about 60cm centres. The vine eyes are screwed into the wall right up to the eye to make them strong. The exact spacing of vine eyes can be adjusted according to the perceived weight of the climbers to be grown.
Window boxes are planters which are installed either on a window ledge or beneath a window using supportive brackets. There provide a relatively easy solution for greening up walls on houses. From the outside they can look quite formal, depending on the style of box and planting scheme, and from the inside they provide a glimpse of plants and flowers. In some urban areas dominated by terraced housing, roads and concrete pathways they may be the only source of greenery.
Baskets or pots can be hung to create a vertical living screen. Traditional hanging baskets are usually made form metal wire and suspended using chains which are supported by hooks. Hooks can be fixed to timber or brick façades. Terracotta pots are often suspended using ropes which are wrapped around the pots. Again, these can be supported by hooks.
Some containers for plants are purposefully made to be secured to a flat surface such as a wall. Wall mountable pots typically have a flat back side which abuts the wall and these have ready made holes in them for securing them using screws. Wall mounted horse hay feeders can be used for a more rustic effect and these are lined and planted in the same way as hanging baskets. Planter boxes can also be mounted on the tops of walls and secured directly through the drainage holes or by fixing U-shaped brackets to the top of the wall and nestling the planters inside them.
Plants which naturally grow on other plants or on the face of rocks are known as epiphytes. Many are ferns, but they include other plants too. Those that grow on other plants are not parasites but
instead use these other plants for support. They get moisture from rainwater which is trapped between the plant and the support and leaf litter and plant debris lodges between them eventually breaking down to provide nutrients. Epiphytes can be secured to a range of different substrate materials and suspended on green façades.
The espalier is an old technique which refers to training woody plants to grow so as to create a two-dimensional pattern, usually across a wall. It is done by restricting growth on the apical meristems
(the growing tips) which in turn encourages horizontal branching. It was, and still remains, a popular technique for growing fruit trees because it enables them to be grown in smaller courtyard gardens and makes harvesting of fruit more accessible. Grapevines in vineyards are also trained using this technique. The espalier is supported by wires e.g. along a fence or against a trellis or other suitable strong support. The support is usually independent of a building but may abutt it.
Hedges are an age old means of separating land and possibly the oldest form of green wall. Some plants lend themselves well to growing into very tall hedges which can act as screens against noise and wind, as well as neighbouring properties. Others may be used to form hedges which divide gardens or parts of gardens. A hedge grown in front of a wall like an espalier could also be used to create a green façade. A hedge may be formal if created using tight leaved plants and clipped regularly to maintain a tight shape. It can also be less formal if lose growing plants are used.
Arches are usually made from stainless steel or powder-coated metals, although wooden arches are also very popular. An arch used to frame an entrance into a building provides a perfect support structure to grow climbing plants and enhance a green façade. Arches don't have to just be used to walk through. They can also be used side-by-side against a long wall of a house, or a garden wall, so as to create a
Terraces are a means of making use of steep sites. Terracing involves creating steps in the land on steep slopes. These are then planted to create a green slope. The green wall effect they produce is
best perceived from a distance. The closer the terraces are created, the more seamless the plant growth will look.
Learn More with ACS
With a large selection of gardening and horticulture courses, including Green Walls And Roofs, you are sure to find a course to suit your personal interests or career goals. Learn from our expert tutors, and study when and where you choose to. Our courses are studied by distance learning and you can start at any time!
If you have any questions, get in touch with our highly knowledgeable specialist tutors today - they will be pleased to hear from you and to answer your questions.
More from ACS
Over 150 short courses, certificates and diplomas covering landscaping, crops, plants of all types and general gardening.