A wetland garden taking shape in the Constantia Valley is helping to breathe biodiversity back into the greenbelts.
The site off Brommersvlei Road, on the Diep River and Alphen trails, was previously a roadworks camp.
The Friends of Constantia Valley Green Belts group is funding the project. Constantia residents started the non-profit group, which is affiliated to WESSA (Wildlife and Environment Society of South Africa) and works with Working for Wetlands and Source to Sea. It concentrates on caring for the green belts and replacing alien vegetation with indigenous.
Most of the greenbelts along the various watercourses – including the site of the rehabilitation garden – belong to City Parks, and City environmental manager Fay Howa has worked with the Friends group.
Alex Lansdowne, a restoration horticulturist and plant conservationist, is also part of the project, and he refers to the Constantia greenbelts as “ecological deserts”. Few species, he said, could live in them because of poor habitat conditions.
The rehabilitation garden would create a pocket of biodiversity on the greenbelts, he said.
Planting began last August after invasive Kikuyu grass was cleared. Ponds were created and the wetland was shaped after which 50 plant species – including some threatened ones – were added. Many were chosen for their ability to attract wildlife or support other plant species. The garden is part of The Alphen greenbelt rehabilitation project to transform a highly degraded, unsightly area into a self-maintaining, locally endemic fynbos-wetland garden.
“We went from one dominant and invasive grass species and a few weeds to having about 50 locally endemic species that would have occurred in that ecosystem before it was degraded,” Mr Lansdowne.
A handful of threatened species in the garden told the story of conservation gardening in Cape Town, he said.
“There is an extinct-in-the-wild Erica as well as Red List threatened proteas and other species.”
Colen Walker, of The Friends, said that the garden would also reintroduce the peninsula granite fynbos.
Mr Lansdowne said the ponds showed how the garden was developing.
“The ponds are a unique ecosystem in themselves as they are seasonal pools, as opposed to the moving water in the river. Within two weeks of the ponds filling, we already noticed thousands of tadpoles.
“These wildlife-plant interactions prove the garden is working to enhance the ecosystem. This garden proves that the best model to get conservation done in small open space is through community conservation and local custodianship.”
The restoration of the area and seasonal pond system would become a biodiversity pit stop for many creatures moving through the green belts, he said.
With further funding the group hoped to create similar gardens, he said.
Mr Walker said the site had established itself and more species would be added.
They had removed some of the pioneer species – planted in the beginning to protect smaller plants – because they had grown very quickly and become quite bulky. The bottom part of the garden is a wetland while the upper level is drier.
The garden is also in the shape of a circle and for this reason, many have mistaken it for a second mandala, similar to the Grootboskloof Mandala on the greenbelt that joins the bridge on Firgrove Way, across the Blue Route. The mandala is the brainchild of Caitlin von Witt, who clarifies that the two projects are not related.
Ms Howa did not respond to queries by the time this story went to print.