Oak Lawn Rain Garden
Oak Lawn Rain Garden
Oak Lawn Rain Garden
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Did you know that tree roots are a first line of defence against flooding? Though it recently sickened and had to be removed, for the last several decades a large Acer pseudoplatanus (sycamore) tree stood on this spot. Without its extensive living root system in this hillside, more water will flow toward the John Hope Gateway building during storms.
What are we learning? How are we adapting?
In 2024, the RBGE NBS team partnered with Heriot Watt University to create a hydrological map of the garden grounds. The map simulates a heavy rainfall. Any sites on the map that show blue are areas where water pools, which tells us where we can be vulnerable and therefore where we need to plan nature-based solutions for the future. The John Hope Gateway building is one of those low points.
This newraingarden continues to use the power of nature and the life of plants to help combat flood risk for buildings and improve the ecosystem. The drain across the path opens into a small stream in the lawn, where the contour of the land and strategic placement of plants guides the water to slow down before emptying into a wallow, slowing down and redirecting stormwater where it can safely pond while providing for nature. The central tree is elevated on an island, while the surrounding plants are chosen for the varying water conditions that will exist in this space. The plants are chosen to be suitable for both the water conditions and the understory of a woodland. The central tree is a Quercus variabilis (cork oak), integrating well with the existing trees of the oak lawn.
The Nature Based Solutions, Horticulture, and Education teams of the Botanics partner together to build an understanding of our changing climate into our curriculum. This new forested raingarden was designed in part by RBGE horticulture students with supervision from NBS scientists and senior supervisory horticulturists.