Published on Wednesday, April 05, 2017
Planting season is upon us and one thing that is on every farmers’ mind is how to maximize their return on investment (ROI) for this season. One obvious way to increase ROI is to decrease your input costs. If you are running any kind of starter fertilizer, you can improve your ROI through proper calibration. You might be thinking, “why do I need to calibrate my starter fertilizer system this year” or “it worked fine last year so I’m sure it’ll be fine this year”. The real question however, is what is it costing you by not calibrating?
Becks Practical Farm Research (PFR)® has multi-year, multi-location data that shows a positive ROI for some common formulations of starter fertilizers at specific rates.
When looking at this data, you can see the benefits that an in-furrow starter can offer; but what are you missing if you don’t calibrate and apply it at a lesser rate? Take the application of 5 gal. of Puregrade® Diamond 6-24-6 for example. Do you think you could achieve the $11/A. or $15/A. ROI by running too low of a rate? While it is possible, with the tougher market economy why risk it? But, what would your results look like if you were to over apply your starter fertilizer?
One obvious problem with over applying an in-furrow starter would be an increase in your input costs with the potential of decreasing your ROI. One hidden factor that most people don’t usually think about is the salt index of the fertilizer. Most farmers know that industry has recommended that we do put more than a combined total rate of 10 lb./A. of nitrogen (N) and potassium (K) in-furrow due to the possibility of salt injury under the right weather and soil conditions. For example, a common in-furrow starter product of 9-18-9 at a rate of 5 gal./A. could put your crop in danger with a total of 9.9 lb./A. of N and K. If you were slightly off on your starter fertilizer application rate and put down 5.5 gal./A., you’d be looking at 10.98 lb./A. of N and K. Similarly, if you were to apply 7 gal./A., you’d be looking at a combined rate of almost 14 lb./A. of N and K in-furrow! It’s not a guarantee that this will result in stand issues due to fertilizer burn, but if the weather becomes dry after planting there is an increased chance. Planting is the most important pass of the season, so why would you want to take the risk of lowering your yields before the crop is even in the ground? Now that we’ve established the reasons why calibrating your starter system is important, here are some tips for calibrating your planter.
The first thing you need to do is take out the screens and clean them thoroughly and, once they are clean, put them back and run hot water through the system. The hot water will remove any sediment from the lines. Then, go ahead and pull the tips (orifices). When you pull your planter out for spring planting, you should be ready to drain the antifreeze from last winter and put the orifices back in. You will want to run hot water through the system again while you check to see if the Red Balls in the manifold system are running equally. If they aren’t, check for leaks or kinks in the lines. If you run micro tubing this is one more thing to check if the balls are not running equal. Sometimes, when the line is cut, a bur is left on the inside diameter of the tube causing that row to run at a lower rate.
Once you are sure that all the rows are operating equally, you are ready to start the calibration process. Make sure to calibrate with the product that you are going to use for the season and not just with water because it is convenient. If you are using water as a carrier instead of fertilizer, then go ahead and calibrate with water. You will need to choose an orifice before starting, and it is recommended to choose one based on the weight of the solution you plant to apply as well as the anticipated pressure, gallons per acre, and speed. For reference, you can find product weights on page 141 of the TeeJet Catalog 51A. To calculate your gallons per minute (GPM) before calibration, you need to do some quick math.
Gallons Per Acre (GPA application rate) X MPH (planting Speed) X W (Row Width)
5940 (Which is a constant)
Once you have your GPM, you can select an orifice based on a given pressure (at the orifice). These selections can be found on page 49 in the TeeJet Catalog. Then, you will need to dispense your product into the product tank and place containers under every row unit. You will also need a stopwatch, a measuring container, a calculator, and a second set of hands. With one person in the cab of the tractor and the other catching product from the row unit, turn on the system and run it at the desired operating pressure. Set your stopwatch for one minute and have the person behind the planter start catching the product out of a row unit. Once you have reached one minute, convert the ounces to gallons. This will be your GPM. We typically recommend testing at least half of the planter and then average the GPM from the tested rows. Once the GPM is determined, you can calculate the GPA at that pressure.
GPA: 5940 X GPM
MPH X Nozzle Width
Your GPA is the rate at which you will apply your starter fertilizer at the pressure and speed you have selected. If you do not calculate the GPA you are needing, you can always adjust your speed or pressure, but you will need to do a catch test again.
Setting up a Microsoft Excel or Google sheet through Google Drive can make it easier to keep records of the tests you conduct. The great thing about Google sheets is they can be accessed anywhere via cell phone, iPad, or computer. We like to build the formulas right into the sheet, so that when we enter our GPM values, the GPA automatically calculates. The chart below is an example of the sheets that we use, and as you can see it details all the rates and speeds for the given product we will be using throughout the season.
Once you determine the rate you need to apply, make sure to highlight that row in a different color. At this point, your calibration is completed and you should know what speed to drive and what pressure to apply the product.
Always remember to keep your lines and strainers clean. If your planter is going to sit for an extended amount of time, it is best to either leave it full or rinse it out. If the system isn't full, oxygen will start to crystalize the fertilizer in the lines, which in turn will cause plugging issues.
Practical Farm Research (PFR)® is a registered trademark of Beck's Superior Hybrids, Inc. Puregrade® is a registered trademark of The Andersons, Inc.
Author: Jim Schwartz
Categories: PFR, PFR Reports
Tags: planting, Practical Farm Research, PFR, PFR Report, ROI, Planter Calibration, Starter Fertilizer