Fertigation is not a new term in agriculture, but its popularity has increased dramatically over the past few years for good reasons. The most common form of chemigation, fertigation, is injecting fertilizer directly into the irrigation water. Depending on the growing environment, these systems can be fundamental to extremely complex. From bulk injection using gas-powered engines to fully automated venturi-based systems, the options can be overwhelming. But for growers looking to step up from the most basic form of fertigation to a more precise and easier way to use the equipment, Dosatrons are a perfect solution.
How it works
Dosatron non-electric injectors work using volumetric proportioning, ensuring that the chemical mixture remains the same regardless of pressure and flow variations. When water enters the Dosatron, it triggers the hydraulic motor, which begins moving up and down inside the injector’s body. The Dosatron draws fluid up from the concentrate tank on the upstroke, with an action similar to a hypodermic syringe. The concentrate is displaced into the mixing chamber on the downstroke, where it mixes with the water flowing through the unit. Then the water-and-chemical mixture is discharged into the water lines.
A typical installation of Dosatrons involves plumbing the injectors inline. This is where the total system flow rate passes through each injector. Therefore, Dosatrons are commonly used in indoor and greenhouse growing applications where flow rates are typically lower. Injector sizes of 14 gallons per minute and 40 gallons per minute are typical. When installing these systems, it is important to include water hammer arrestors and/or air vents when possible to protect the equipment from pressure spikes. We also recommend installing a bypass line that allows for clean source water to be used if an injector needs to be serviced. Considering the type of fertilizer or acid to be injected will determine which ratio unit to be used and how many mixing chambers to be used.
For higher flow applications, there are Dosatron units that can handle 100gpm, 132gpm, and 400gpm. On outdoor applications, these units are often installed inline or in parallel. Units installed in parallel split the total system flow across several different units. We have successfully accommodated up to 1200gpm using three D400 in parallel. With this installation, it’s important to remember that for the most accurate injection possible, each fertilizer would require a Dosatron on each parallel line, or the flow going through each line must be split evenly using meters or flow control devices.
For growers looking for a simple and reliable step towards automated fertigation, Dosatrons are a perfect choice. The no electricity requirements make it a good fit for remote farms and a low-cost investment for growers looking to spoon feed and cut back on labor costs.