The big drip ~
A win-win situation for plants
Irrigations systems can save money, time and water

July 16, 2009

by Charlie Neumeyer,
Victoria County Master Gardener

edited by Charla Borchers Leon,
Victoria County Master Gardener
Normally, when you have a dripping faucet, it is a bad thing. But when it comes to irrigation, dripping is a good thing. A drip irrigation system in your vegetable garden, flower beds and planting areas, can save money and time, but, more importantly, it can save water. With our current dry conditions and high temperatures combined with strong winds, it is more important than ever to conserve when watering.
If you opt to install a drip system and attach it to your hose bib, you will have to include a splitter, a timer, a pressure reducer and a hose connector.
In-line drip systems

At the Victoria Educational Gardens, the Master Gardeners have installed a drip irrigation system on the east side of the gardens (nearest the airport runway). The turf demonstration area utilizes the traditional spray-type irrigation, but all of the planting areas are watered by the drip system. The display area near the pond shows one method of drip irrigation to water the flower beds.

Designed by Master Gardener Ron Gillig, the in-line drip hose encircles the specimen plants in these beds and in the rose areas whereas the in-line hose is snaked through the more densely planted beds to provide complete coverage. The hose used in the gardens has built-in emitters, spaced every 12 inches, allowing for even distribution of water throughout the beds.

Systems with insert emitters

A second type of drip system allows the user to determine the spacing on the emitters. With this system, the tubing is laid on the ground and the emitters are placed near the plants that are to be watered. This type of system is more efficient in plantings that contain large plants that are relatively far apart. Examples would be hedges planted in rows, or beds that feature specimen plants as opposed to mass plantings.

Why drip systems save water

Given the high temperatures coupled with strong winds that we have been experiencing lately, traditional sprayer head systems may be less efficient than the drip systems. According to Dr. Dotty Woodson, a water resources expert, a drip irrigation system is 90 percent efficient whereas a well-maintained spray irrigation system is 75 percent efficient. Unfortunately, Woodson says, most spray systems are poorly maintained and only about 55 percent efficient.

Two ways to lose water

Whenever you put water into the air as you do with the traditional irrigation systems, you waste some water. If the wind blows, the fine droplets of water will be blown away from the intended watering site - sometimes into the neighbor's yard or sometimes into the street. The other way water is lost is through evaporation. This can be a real problem if the sprinkler is running in the afternoon on sunny days.

Drip systems solve these two problems. Since the water dribbles onto the ground, there is no opportunity for the wind to impact where the water goes. Further, according to Ian McBeam, owner of Majestic Irrigation and Landscaping Service in Victoria, the drip lines should be covered with 3 to 4 inches of mulch so that there is no possibility for evaporation to occur. Since evaporation and loss of water to winds are not concerns, drip irrigation systems can be used at any time during the day or night.

How plants benefit

Some of the benefits of drip irrigation for the plants are obvious. The plants will receive more water directly to the roots in the plant's feeding zone. According to the AgriLife Extension publication, Efficient Use of Water in the Garden and Landscape, a "properly-operated drip system applies a controlled amount of water over a period of time, maintaining the soil moisture at an optimal level which encourages efficient plants." Sprinkler systems can sometimes flood areas which reduces the amount of oxygen available to the plants. This, in turn, stresses and may kill the plants.

A second benefit is plant health. Many plants, especially roses, are subject to diseases like powdery mildew and black spot. Because drip irrigation does not splash water onto the foliage, foliage diseases occur less often, Woodson said. Instances of leaf burn caused by the hot sun on wet leaves are also eliminated.

Do it yourself

While the prospect of working in this hot sun isn't appealing, it is just the sort of weather we have been experiencing that points to the need to be mindful of the amount of water we use. It also should make us mindful of how much water we waste. Depending on how elaborate and large your planting areas are, two people can easily install a drip irrigation system in one weekend. The price of the in-line emitter hose will be about $.50 per foot. The various connectors will cost between two and three dollars. You will also need a pressure regulator, an in-line filter, and a hose or black tubing to run the water from the hose bib to the flower beds. To make it easy on yourself, buy a battery-powered timer to operate the system.

McBeam also recommends the purchase of a soil moisture sensor. This allows you to monitor the amount of moisture in the soil. The materials are available at local irrigation system suppliers. Victoria County Extension Agent Joe Janak recommends conserving even more water by using rainwater. Install a rainwater harvesting system, a small water pump and filter and connect it to your drip irrigation system.

For the do-it-yourself gardener, refer to the several Web sites listed that detail information on different drip systems. Or, just hire a company to do the work for you and sit in the shade sipping a cool glass of iced tea.

The weather-related headlines since last month are a wake-up call for action. The Guadalupe River has hit a critically low level, and may remain there. There is no significant rain in the short-term forecast; the long-range forecast is not much better. Temperatures have been formidable. Installing and using a drip irrigation system is a win-win situation. You will have healthier plants and conserve water at the same time.
Despite the heat and dry weather, various blooming bushes and shrubs are thriving with the drip irrigation system installed in Victoria Educational Gardens at Victoria Regional Airport.
This portion of VEG is used to display the in-line drip irrigation system. The plumeria tree is treated as a specimen plant in this area with the hose encircling the plant.
. A publication overviewing different types of irrigation systems with detailed instructions and diagrams on how to plan for and install a drip system
. An article on irrigation and all other phases of landscape design
. A commercial source that gives some idea of the costs and types of available irrigation systems
The Gardeners' Dirt is written by members of the Victoria County Master Gardener Association, an educational outreach of Texas AgriLife Extension - Victoria County. Mail your questions in care of the Advocate, P.O. Box 1518, Victoria, TX 77901; or, or comment on this column at