In past posts I’ve alluded to the need to use our most essential natural resource— water—in a more sustainable manner. All over the United States (and across the world) the demand for clean, fresh water is booming, while the potential sources of supply are, thanks to pollution and mismanagement, actually shrinking. This is one of our society’s greatest challenges: how to make the water supply stretch to suit all of our needs without draining rivers, streams, and aquifers.

Gardeners can have a big impact on this situation, especially if they adopt Robert Kourik’s book Drip Irrigation for Every Landscape and All Climates as their irrigation operator’s manual. Studies have found that landscape irrigation can account for 40 percent or more of total urban and suburban water consumption. And as Kourik points out, drip irrigation, because it is so much more efficient at delivering water to the root zone of plants than sprinklers and other types of last-generation watering technology, can reduce the number of gallons you use by 50 to 70 percent. You do the math.

Water conservation, although important, is only one of many reasons why Robert Kourik advocates drip irrigation. It’s pinpoint accurate at putting water where you want it, which means that you can nurture desirable plants without soaking adjacent areas and creating opportunities for weed invasion. Unlike sprinklers, drip systems don’t wet plant foliage, which can reduce the incidence of fungal diseases such as blackspot on roses. Drip irrigation systems water slowly so that the moisture soaks into the soil without the kind of surface flooding sprinklers commonly cause—such flooding not only wastes water it also damages the soil’s structure. Finally, the slow but steady nature of drip irrigation has been proven to increase the yield of vegetable and fruit plantings. Surely it must have a similar effect on flower beds.

There are many books on the market about drip irrigation, but Kourik’s is unique in the clear, accessible simplicity of its prose and illustrations. For a technophobe like me, designing a drip irrigation system with valves and filters, tubing and “emitters” is an intimidating prospect. Kourik manages to make this seem simple. He does the same for the processes of installation and maintenance, too. What’s more, his information is as fresh as it gets. Though he has been experimenting with drip irrigation since the 1980s and wrote his first book on the subject in 1992, this current manual (copyrighted 2009) sprang from a thorough rewriting and updating and reflects the latest data, materials, and techniques.

I once heard iceberg lettuce described as “textured water.” That’s actually a pretty fair description of plants in general. Water comprises more than 90 percent by weight of many species—even a desert-dwelling prickly pear cactus is 85 percent water. How you water—when, and how much—is one of the most potent tools a gardeners have to influence the growth and character of their landscapes. With conventional irrigation, this tool is, at best, a blunt instrument. In Drip Irrigation for Every Landscape and All Climates, Robert Kourik shows you how to turn it into a precision instrument.