Kip reviews Rain Gardens by Nigel Dunnett and Andy Clayden
Not long ago I was listening to a talk-radio show where the world's petroleum supply was being discussed. A caller made the point that a more immediate crisis involved another commodity altogether: fresh water. He also mentioned that most of the available fresh water is in the U.S. and Canada. It was nice to hear that, but as many North American gardeners are well aware, this doesn't mean water is inexpensive or free from outdoor-use bans in numerous communities. The authors of Rain Gardens sum up the problem:
Our demand for water is growing dramatically at a time when in many areas of the world its supply can no longer be guaranteed.
We have now come full circle [from the ancient Paradise Gardens of the Middle East], with water once again viewed as a finite and unpredictable resource...
As the subtitle of the book (Managing water sustainably in the garden and landscape) suggests, there is a pressing need for implementing sensible conservation practices if we are to continue building and maintaining gardens—and who would want to put an end to that? "Without water we wouldn't have gardens," the authors write, and I would add, "Without gardens we would still need water." Although water conservation may seem a matter more suited to large-scale planning in towns and cities and in the countryside, the focus of Rain Gardens is on small-scale actions at an individual level. As it turns out, in years of normal rainfall, landscape irrigation accounts for 43 percent of all residential water use in the western U.S. and 26 percent in the east.
Unlike many other environmental initiatives that challenge us to change our lifestyles, often at personal cost... , rain gardens have the potential to be beautiful additions to our environment, and bring with them a host of other benefits.
Technically, a rain garden is a planted depression that is designed to take as much as possible of the excess rainwater run-off from a building and its associated landscape, but the most intriguing idea (to me) covered in the book is the "green roof," a layer of living vegetation installed on top of a building. They are best known when used on a large scale—on schools, office buildings, and factories -- but they are equally suitable for sheds, garages, and other small structures. A green roof not only reduces water run-off, but can also become the central focus of a garden. General instructions for creating several types are provided.
Whatever class of rain garden seems most appropriate when your own abilities and the needs of your landscape are taken into consideration, the installation of one will surely provide great aesthetic satisfaction while creating conditions beneficial to wildlife and biodiversity—a win-win situation. Let the rains begin!
Kip Anderson has been the Victory Garden's head gardener for over 20 years.