Featured Stories

Other Pamplin Media Group sites

Wise - and not wasteful - ways to water


Drip irrigation may be best course for do-it-yourselfers

by: PAMPLIN MEDIA GROUP: JONATHAN HOUSE - A soaker hose has been described as a poor mans drip-irrigation system. Its a cheap and easy way to water shrubs and gardens, and is easily moved around as needed.   Spring has arrived and that means the rain is going to stop. Really, it is.

And when it does, Portland gardeners will be faced with getting water to their blueberry bushes, rows of carrots and snap peas.

Hosing down the garden takes time, and sprinklers attached to those hoses end up spreading water everywhere. Drip- irrigation systems target the places you want to water, but require equipment and, in most cases, money to install.  Somewhere in the middle is the option of a soaker hose, sometimes called a poor man’s drip irrigation.

Each alternative carries an environmental cost that should be considered along with out-of-pocket costs. The most obvious one is wasted water.

According to the U.S. Environmental Protection Agency, 30 percent of all the water consumed in the United States — 7.8 billion gallons a day — goes toward outdoor use, mostly for lawns and gardens. A typical suburban lawn consumes 10,000 gallons of water, not counting rainfall, a year.

Manual watering with a hose usually is the most water-efficient method for shrubs, trees or gardens. When you water manually, you target the plants that need to be watered and don’t waste water in surrounding areas. Also, you can check the weather report and not waste water on days it’s going to rain anyway.

An underground sprinkler system on a timer uses 35 percent more water than a hose, according to the EPA. A drip- irrigation system uses 16 percent more water than hosing.

So if all you’re worried about is conserving water, and your garden is small enough, get out there with your hose and water the plants yourself. It will do you and your plants good, says Weston Miller, community and urban horticulturist for the Oregon State University Extension Service.

Aside from the fresh air and exercise benefits, “It gets people outside observing their plants,” Miller says. Gardeners spend more time enjoying their gardens and monitoring for pests, Miller adds, and fewer pests mean less need for pesticides, another environmental plus.

When a hose isn’t enough

But watering with a hose isn’t practical if you’ve got a large garden or a lawn, or little free time in the early morning, the ideal time to water. And that’s where determining the most sustainable solution gets complicated.

Sprinklers, either oscillating varieties attached to hoses or stationary ones built into the ground, don’t take much of your time. They also get everything wet, which has its problems, Miller says. 

Sprinklers also deliver water to weeds and sometimes sidewalks. So that time you saved not having to water with a hose can be spent pulling up faster-growing weeds. Also, Miller say, sprinklers leave water on leaves, where it can encourage fungus and other plant diseases to grow.

That leaves drip irrigation, set on a timer to turn on first thing in the morning. An installed drip-irrigation system will place the water at the base of plants you want watered, so little water is wasted. A small self-installed system can be had for $50.

Drip-irrigation systems are more efficient than sprinklers, Miller says. But they have their drawbacks.

Jason Garvey, who until recently owned Portland Purple Water, a company dedicated to water conservation, says an installed drip system makes it hard to move the plants from year to year. Once you’ve set the emitters to dispense water at particular spots you’ll have to dig up the system and move the emitters if you change the locations of plants.

Going low-tech

That makes above-ground soaker hoses appealing. They may be imprecise, but they’re inexpensive, “and you can put it in place in a matter of minutes,” Garvey says. Soaker hoses work best for such plants as vegetables, which are set in tidy rows, he says. The little holes in the hose that determine where water will drip are pre-set, so you can’t target plants scattered around your garden.

Soaker hoses degrade over time and need to be replaced. The amount of water they deliver can vary, depending on household water pressure, and even whether somebody inside is taking a shower. When water pressure is low, plants at the end of the soaker hose’s line may not get their fair share.

Adding up all the variables, Miller and Garvey both lean toward drip-irrigation systems for all but the smallest gardens. They can be expensive, but Garvey says most homeowners can install their own. A control valve will take care of the differences in water pressure and a timing system will deliver an early-morning soak.

Garvey recommends website dripdepot.com to buy drip systems and for simple, do-it-yourself directions. Garden stores also can make recommendations.

“People are capable of doing this,” Garvey says. “It’s not overly complex.”