When homes are designed and built, measures are taken to divert rainwater away from the house and off the property. Structural changes on the property or in the surrounding environment may, however, alter the volume and flow of water entering a property and very often necessitate modifications to the initial drainage design.
The garden featured in this article is in a residential estate in Centurion, Pretoria. The house is built on a slope and the front door is positioned slightly lower than the 200-square-metre front garden, which is open to the street. The property was incident-free until a flooding incident occurred.
A few months before the event, a speed hump had been installed in the street. While this helps to calm the vehicular traffic, it obstructs the course of rainwater and water flows onto the property during a downpour. The front garden was mainly lawn, so rainwater simply washed down the slope and pooled against the house. When the water didn’t seep into the soil quickly, it entered the house, causing extensive damage. A drainage point was installed at the lowest point of the garden to capture water and redirect it away from the front door. Realising that their garden needed a facelift, the owners asked us to design a low-maintenance, water-wise scheme that factored in the possibility of the occasional flow of water through the garden.
The homeowners had originally planted up their garden over several years and it contained an eclectic selection of plants that were probably chosen according to trends current at the time. This resulted in the space lacking a synchronous theme, with a combination of tropical plants and desert and forest species. Some of the variety included a queen palm Syagrus romanzoffiana, a pair of ponytail palms Beaucarnea recurvata, a pencil conifer Juniperus scopulorum ‘Skyrocket’, a sago palm Cycas revoluta, a New Zealand cabbage tree Cordyline australis and a row of potato bush standards Solanum rantonetti. There were no groundcovers and this collection of plants provided very little incentive for any local wildlife to be attracted to the garden.
Our first decision was to remove the lawn, as it required a good deal of water and was a high-maintenance element. We created a stony, dry river-bed to channel water from the road towards the drainage point. The slope was contoured to help slow the flow of water and direct it to the catchment area, and a steppingstone path was laid to wind through the garden towards the tap. The plants were selected to provide interest and to meet the objective of creating a miniature bushveld river scene. Height, screening and bird perches are provided by trees: wild peach Kiggelaria africana, lavender tree Heteropyxis natalensis, tree fuchsia Halleria lucida and a monkey thorn Senegalia galpinii.
We included lower-growing, spreading groundcovers such as African daisy Arctotis stoechadifolia, aptenia Aptenia cordifolia, variegated plectranthus Plectranthus madagascariensis and silky cotula Cotula sericea along points of the path and river course. To cater for seed-eating birds, we planted grasses, namely weeping anthericum Chlorophytum saundersiae, common rush Juncus effusus and Ngongoni three-awn Aristida junciformis. They look magnificent when blowing in a breeze and require minimal maintenance. Nectarivorous birds can feast on the wild dagga Leonotis leonurus, crane flower Strelitiza reginae, tree fuchsia and three aloe species that flower at different times of the year. Seasonal colour is provided by hardy favourites such as agapanthus Agapanthus praecox, yellow wild iris Dietes bicolor, jade plant Crassula ovata and the September bush Polygala myrtifolia.
The garden is young and still evolving, but in the past three years it has begun to teem with life. At least one plant species is in flower at any time of the year and the garden has become home to bees, butterflies and spiders. Being barely a kilometre from the Zwartkops Resort, a large, undeveloped area along the Hennops River, it is now attracting regular visits from numerous birds. The practical drainage solution has become a feature in its own right. Hopefully it will set a trend for the estate, as passers-by who watched the transition recently commented that although they were initially sceptical, they now see the vision behind this lawn-free, indigenous garden.