IRRIGATION FOCUS- FERTIGATION: One-a-Day Fertilizers

Across the United States each morning, millions of moms and dads begin the day by handing their children brightly colored, fruity tasting vitamins fashioned in the shape of cartoon characters. Each dose, composed of the right mixture of vitamins and nutrients, keeps the children healthy and growing.

Jeff Prink, park maintenance supervisor, City of Aurora, Colo., does the same thing for the parks and recreation areas in his care. For the last two years, Prink has experimented with fertigation, the recurring delivery of small amounts of liquid fertilizer and soil nutrients through an irrigation system. The process has been used for decades in the agricultural and golf course markets but only recently made its way into residential and light commercial settings.

In the past, fertigation systems were too expensive, too complicated or too cumbersome to make sense for residential irrigation contractors and homeowners. However, several manufacturers recently have developed pared-down fertigation systems targeted at the residential market. These units range in cost from less than $200 to $1,500, depending on the system, the market and the size of the landscape on which it will be used.

FERTIGATION ADVANTAGES. The chief benefits of fertigation are:

"The biggest benefit I see is how weak the fertilizer is," Prink observes. "By the time you are putting it into the irrigation, it is so diluted that it becomes less harmful to the turf."

Prink also has noticed healthier root zones in the turf he fertigates. "The fertilizer is right there in the water, so it gets in the root zone well. I’ve seen first hand some improved root zones."

FERTIGATION DISADVANTAGES. What makes fertigation such a logical proposition – use of an existing irrigation system to spread fertilizer – can also be the chief downside of the technology. The fertilizer only goes where the water goes, so if the irrigation system is poorly designed and achieves lackluster uniformity, the fertilizer will be patchy as well.

"Application of the fertilizer is only going to be as good as the uniformity of your irrigation systems, which on a residential system is probably not all that great," says Brian Vinchesi, president, Irrigation Consulting Inc., Pepperell, Mass. Likewise, high heat or wind, the same forces that evaporate or diffuse irrigation water, can have similar negative effects on fertilizer applied through a sprinkler.

"If I were a contractor, I would be concerned with the liability of it," Vinchesi adds, referring to the combination of fertilizer in irrigation water. Reduced-pressure backflow prevention devices are required to prevent contamination of the water source, and there is the concern about the liability of fertilizer carried by the wind into a neighboring property.

Before going too far with fertigation, contractors should carefully investigate state and local codes on the issue. In many states, certifications and licenses are required to apply fertilizer. "It may be that since the homeowner owns the system, they don’t have to be licensed, but that’s certainly a question I would want to ask somebody," Vinchesi notes.

Fertigation also involves increased sales activities. It is one thing for a contractor to sell a customer a periodic $35-fertilizer application but quite another to ask a homeowner to purchase a $500 fertigation system they may not entirely understand.

Jason Maddox, agricultural and irrigation sales representative, Dosatron International, Clearwater, Fla., says some contractors are designing programs to help homeowners defer upfront costs by spreading fertigation equipment and installation costs over time as part of a monthly fertilization contract. And, so far, Maddox adds, the key customers have been upper income residences and light commercial accounts, which are less cost conscious.

MARKET GROWTH. Though residential fertigation systems remain somewhat rare and limited to upscale clientele, there’s no question the idea of fertigation is growing, says Ned Lipps, chief executive officer, Fertigator, St. Louis. Mainstream irrigation distributors, such as John Deere Landscapes, Ewing Irrigation, Horizon and United Green Mark, have begun carrying multiple brands of residential fertigations systems.

"I think in the next five years it could be our biggest market," says Jim Fields, horticulture sales manager, Dosmatic U.S.A., Carrollton, Texas. "The retrofit market is where a massive amount of business is going to take place in the next few years."