The Facts About Water Features and Irrigation Systems: An Interview with Barry Friesen of Dawn Landscaping Inc.

Please tell us a little bit about your company and the services you offer.

Dawn Landscaping Inc. is a landscaping firm constructing and planting beautiful gardens in California's Alameda and Contra Costa Counties. The firm works closely with landscape architects and designers in the creation of harmonious garden plantings which have been featured in many articles in nationally known magazines and books. We build decks, retaining walls, patios, screens and fences. We install irrigation systems, outdoor lighting, planting and water features.

What are some of the most popular water features for homeowners in Northern California?

For formal gardens fountains are the most popular. They are usually purchased from retail outlets like Pottery Barn and installed by the landscape contractor, including footings, electrical work, plumbing, pumps and switching. For informal gardens more natural water features are constructed from scratch including excavation, rubber EPDM liners, rocks and boulder placement, waterfall construction, pumps and plumbing, and selecting and arranging plantings around the feature to achieve a natural effect.

What are some of the basic choices a homeowner needs to make for a new irrigation system?

There are two basic types of irrigation: drip and spray. Drip systems water the plants and not the area between the plants so there are less weeds and 50% of the water is conserved compared to spray systems. Spray systems are the traditional way to irrigate a garden and there are many types of heads that distribute the water, such as rotor, impact, matched precipitation rate spray heads. Microspray heads are a hybrid between drip and spray systems which shoot out water to small areas (< 3').

Can you briefly talk about the new water-conserving controllers that are available?

A new generation of irrigation controllers have been produced in the past 10 years that are designed to save on irrigation water. Some manufacturers have models that are installed with a small weather station in the garden that regulates how much water is applied to the plants depending on the temperature, wind and recent rainfall. Other manufacturers have models that are controlled by weather stations in other nearby areas and the data is transmitted to the controller via the Internet or via radio signals. These controllers are generally called ET (evapotranspiration) controllers, which replace only the amount of water used by the plants. These controllers can be used for drip or spray systems and help the homeowner to conserve water. Some controllers have sensors which are placed in the soil near the plants and only allow irrigation when the soil is dry. Other devices are available that can be attached to any controller, and they stop irrigation when it is raining or stop irrigation when it is too windy.

What are some of the biggest challenges when it comes to installing a water feature or irrigation system?

The biggest challenge for a water feature is how to provide filtration so the water doesn't get dirty and algae doesn't grow. It can be done with screens, sand and gravel beds, biological media, UV lights and chemicals. The biggest challenge for a drip irrigation system is being sure that the water is properly filtered and the pressure is regulated with the proper devices. The emitters which drip the water out to the plants have very small orifices and need clean water to operate properly. Spray systems have larger orifices that spray water so the main challenge for them is to regulate them not to apply too much water to cause runoff. This can be done by proper timing by the controller or using nozzles that have lower precipitation rates.

What advice can you give to people about proper maintenance for these?

At least once a year irrigation systems should be checked by an irrigation contractor. The drip lines should be flushed, pipes should be covered by mulch or buried, emitters should be checked for proper flow. Spray head should be checked for proper direction of spray and radius of spray. Also plants should be pruned so the water is not deflected by the foliage. As the seasons change the owner or the gardener should change the timing of the controller if the controller does not do that automatically.

What's the best way for people to contact your company?

See our website . Our phone number is 510-385-5139 and our email is dawnlandscaping@hotmail.com.