Drip tips

Features - Irrigation

This increasingly popular way of irrigation has its fair share of rules.

February 10, 2014

Rising water costs and changing regulations are driving the popularity of drip irrigation in some parts of the country. However, those that don’t have to comply with regulation or deal with an increase in the cost of water aren’t necessarily opting for it.

In North Texas, Chris Lee says that he’s been selling a lot more drip irrigation these days. “There are a lot of reasons it’s a better system,” says the president of EarthWorks. “There’s much less run-off and it’s horticulturally the better option for the plants. But it’s the drought and water restrictions that have driven its popularity here.”

Lee says that rapid population growth, which is outpacing the region’s reservoir development, has led to a need for efficient water usage. For EarthWorks, that’s meant more xeriscaping and more drip installation, even in retrofits.

Wayne Nolan, president of Nolan Plumbing and Irrigation in Jacksonville, Fla., says he’s seeing an increased interest in drip as well. But he also says it’s being driven by necessity. Changing codes are “forcing many to accept it,” Nolan says.

And where codes haven’t changed and the cost of water is still low, drip isn’t getting the same interest. Paul E. Morgan, principal, The Rain Harvest Co., in Snellville, Ga., says he hasn’t seen any major increased interest in drip installations. “The only significant increase in drip installation requests would be for the commercial market where it is required by municipal code or performance requirements as dictated by LEED, Green Globe or Earthcraft,” Morgan says. “Here in the southeastern U.S., the cost of water is still quite low and plentiful due to recent abundant rainfall.”

Though clients’ interests in water conservation is typically driven more by their budget than their concerns with saving water, many companies like Morgan’s have still gone the route of only installing drip. “It’s the only type of irrigation we install because our company is driven by the promotion of water stewardship,” Morgan says. “Drip surface, and especially subsurface, are the only options.”

The does & don’ts of drip.

Though drip hasn’t taken a stronghold in all parts of the country, some say it’s trending toward increased interest as the cost of water inevitably rises in more regions and codes continue to evolve. As that happens, it will become necessary for more irrigation contractors to get comfortable with drip installation. Those that are already familiar with the process say there are some key “does and don’ts.”

Before even starting the process, Nolan says it’s a big “do” to get a soil test done. It’s a step that many skip but Nolan says that this “often overlooked test” can make a big difference in the success of your installation. “You need to know what type of soil you’re watering,” Nolan says. “The more clay you have, the less water you put out and the further apart you space things. The soil dictates everything.”

The first few installations can be daunting and Morgan admits that a drip system design is more complicated than a conventional one. “The errors in the design of a conventional system are much more forgiving in regards to providing adequate irrigation to all the plants,” Morgan says. “However, if any zone or section of a zone of drip is improperly designed or fails, then you can have dead plant material rather quickly.”

Morgan says that knowing the product you install is also a major “do.” “Know what the pressure ratings for valves and filters are and what the flow rate for the drip line or tape is,” he says. “And use soil moisture sensors. Drip must operate much longer than conventional rotors or sprayers. We find using soil moisture sensors – one per zone – will determine exactly how long the run time should be.” In terms of “don’ts,” Nolan says the biggest lesson learned was to be more diligent about burying and securing the system. “The biggest complaint we’ve had was when they can see it sticking up,” he says. “If not buried or stapled to the ground it can be unsightly. Drip should be out of sight, out of mind.”

However, when it comes to beds that have a lot of change-out for seasonal color, Lee says he’s learned it takes a little extra planning and finesse. “We’ll use an above-ground drip so that we can unpin it in that area, lay the grid back and then do the soil prep,” Lee says.

“Then it must be completely re-pinned in place. We’ve heard people say they can’t plant seasonal color with drip irrigation because of the drip line in the way. That’s not true. You just need to be more careful. We get a lot of compliments about the beautiful seasonal color you’re able to get from drip when it’s installed properly.”

Educate for success.

Morgan says “don’t neglect to educate the consumer.” The client’s understanding will play a significant role in the overall success of the installation. “Drip normally requires less maintenance than conventional irrigation but requires more operation time,” Morgan says. “Remember when you are using drip, GPH – gallons per hour – is the language rather than GPM – gallons per minute. Many of our clients that transitioned from rotors and sprayers to drip don’t immediately understand why the system will be operating for 90 minutes per zone rather than 20 minutes.”

Lee agrees and says one of the biggest challenges in their experience with drip installation has been related to consumer understanding. “People are confused by the fact that they don’t see water percolating above the ground,” Lee says. “They see the soil is a little dry. So we’re constantly running into the issue of people adding water. They keep turning it up until they see the water boggling out and at that point they’ve flooded it.

“The key has been educating people that the ground is going to have some cracks and look dry but that there is plenty of water underneath. If they dug into the soil a little, they’d see.”

It comes down to frequent and repetitive education. “We’re constantly pushing the education factor when it comes to drip,” Lee says. “I think the more we all learn about it, the more successful it can be.”