Deciding which type of irrigation system is the best for your crop is one of your most important decisions as a grower. Water is, after all, the lifeblood of your plants. Without adequate water, nothing else – fertilizer, pest control, weed control or even soil – matters.
But what type of system is best? Sprinkler? Furrow? Drip? Each system has its own advantages and drawbacks. If you've been considering a drip system, it is probably because of its ability to provide water uniformly throughout the field without much waste. However, you may be concerned about the cost effectiveness or that it is difficult to install.
Bob Weimer, a partner at Weimer Farms in Atwater, California, began using drip irrigation in the 1970s. He uses drip tape on his sweet potatoes and above-ground tubing in his almond orchards. As a grower and as a former irrigation consultant he has advice for those considering converting to drip irrigation.
"It's not real time consuming," Weimer says. "You lay out your project with someone who understands pipe and water hydraulics. [They] create a system for you and you evaluate it from there. You need to do a lot of preliminary planning to make it work well, but once you've done that, the drip irrigation system is probably the least complicated to put in, versus a sprinkler system or some other type of system," he says. "If you do your planning right, you're going to minimize your complications."
Weimer says factors to consider when designing a system are elevation changes, hill configurations, soil type, water quality, head losses, crop requirements, and most importantly, the quantity of water that is available. "You need to understand your peak demands during the summertime and whether you're going to have adequate water to take care of the crop during that peak time period," he says.
"You also need to know the quality of water that you're dealing with, whether it is surface water where you're going to have to do a high level of filtration, or whether it's a ground water source such as out of a well, that might need only a minimum amount of filtration. You have to evaluate your water source very carefully."
Weimer has never regretted his switch to drip irrigation. "What you'll like about drip is the productivity. It's a lot of freedom if you're on an automatic system," he says.
In 1990, when Weimer was working in the irrigation business, drip irrigation was rarely used in the San Joaquin Valley. He remembers installing it in a few fields to let growers see its benefits. "I started introducing the drip tape – and it was Ro-Drip at the time – which John Deere has purchased. I brought [it in] and started installing it on a couple of fields and let it promote itself. Within ten years probably 90-95 percent of growers had drip irrigation on their sweet potatoes."
Weimer is quick to say that drip irrigation is not maintenance free. "It took a different level of labor, more training, more technical use of people, but it was effective," he says of their conversion. He cites rodents, tubing moving out of place due to temperature fluctuation and occasional chemical control of algae and bacteria in the lines as potential maintenance issues. But the cost is effective, he says, and stresses that it would not be successful if growers weren't seeing improved quality of yield.
He is also happy with John Deere products. "John Deere is doing things correctly with their selection of product and companies they're purchasing," Weimer says. "We pick the products that are best for us and that's what we like to install. We've had good service – products available when necessary, that's important, to be able to get your product in a timely fashion – and to be able to get the service and help when you need it. We haven't had any issues with that."