Watch the video on Drip Irrigation.
A new-generation of landscape watering can reduce a home's water consumption. Drip irrigation is the highly efficient delivery of water to plants near their base through flexible polyethylene (poly) tubing fitted with water-dripping devices (emitters) and low-volume micro sprays. By slowly delivering water exactly where water is needed, drip irrigation minimizes over-spray, nearly eliminates water evaporation, and reduces water runoff. All of this adds up to dramatically reduced landscape water use—good for the environment and for the homeowner's wallet.
In addition to water savings, incorporating a drip irrigation system into your landscaping has numerous other benefits, such as encouraging healthier plants. Drip irrigation maintains near-perfect moisture levels in the root zone of plants, enabling them to develop deep roots that are more resistant to dry spells. Eliminating over-watering also helps prevent plant disease and minimizes weed growth.
Another benefit of drip systems is that they're flexible and scalable. Drip systems are controlled by hand or by an automatic timer and can effectively irrigate all types of landscape: shrubs, trees, perennial beds, ground covers, annuals, and lawns. A drip system can be used to irrigate new landscaping as well as to retrofit an existing traditional sprinkler system. Also, once a drip system is installed, poly tubing, emitters, and micro sprays can easily be added or removed to accommodate a change in the landscaping layout.
A final benefit of drip irrigation: it can be installed without special knowledge or tools. Drip systems require no trenching; the poly tubing is laid out on the ground and then covered with mulch or gravel to water trees, shrubs, annual and perennial beds, and groundcovers. One exception to the no-trenching benefit is drip systems used for lawn irrigation. In these applications, emitter lines are placed in trenches 4-6 inches below the soil. Trenches can be dug by hand, with a mechanical trencher, or by other means. If practical, the poly tubing for the lawn could be laid before the final 4 inches of soil is spread in the lawn area.
Planning and installation tips
Some important points for planning and installing drip irrigation systems:
- Use enough emitters. The goal when using emitters is to water the plant's entire root system. Large trees can require 12-36 or more emitters, while small shrubs may need only 2-3 emitters. Use a minimum of 2 emitters per plant in case one emitter clogs.
- Space emitters evenly. Locate drip emitters evenly around the plant, staying at least 6 inches from the base of the plant to prevent fungal infections on the main stem. For plants located on a hillside, place the majority of the emitters on the upper side of the plant, allowing water to drip to the lower side.
- Use zoning. During the landscape design, plan to group similar plants together, i.e., separate dry climate plants from humid climate plants; separate trees from shrubs, etc. This will enable you to set up watering zones with watering frequencies best suited for each type of plant. Large landscapes that contain various soil types can be separated by zones, too.
- Install a water filter. To protect the small orifices of the drippers and micro sprinklers from clogging, install a filter at the beginning of the system. Typically, a screen mesh of 150 is recommended, although water quality and type of emitters will affect this recommendation.
- Install a pressure regulator. A pressure regulator will maintain a constant pressure throughout the system, ideally between 10 and 30 pounds per square inch (psi). Systems with too high, too low, or inconsistent pressure won't operate correctly and can leak.
- Work out correct watering schedules. To develop correct watering schedules, pay attention to your plants and adjust the watering to meet their needs. For example, run the system a little longer in hot weather and shorten the run times during cooler weather.
To learn more about Drip Irrigation, visit:
www.dripirrigation.com/newsletter_view.php?newsletter_id=2005-06
www.urbanfarmerstore.com/drip/drip.html
www.dripdepot.com/cgi-bin/drip/before_you_begin.html?id=pDdXkE2W
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