You need to know how to calculate liquid fertilizer rates using formulas instead of how to measure fertilisers. Remember that fertilisers will only be able to do their job well if you use them appropriately for your UK garden and plants. One can assume that fertiliser application will only be optimal if you know the correct rate and measurement.
More so, proper fertiliser management plays a significant impact on the environment and other living things close to the area in the UK. Those who need to use liquid fertiliser can do basic calculations to determine the rate themselves. And as time goes on, you can get used to the concepts, making rate calculations almost like second nature.
Comprehensive Guide On How To Calculate Liquid Fertilizer Rates
Step #1. Understand the formula
The first step in calculating liquid fertiliser rates is understanding the formula. It might be overwhelming to read the formula upon a glance, but it is straightforward. Over time, you’ll get comfortable in inserting the values. For example, read the label to find the N-P2O5-K2O content of your fertiliser.
You’ll also need to do a soil test, which is crucial before handling fertilisers. The test will let you know your target rate and use the ideal fertiliser to provide your plants’ needs. The third part of the formula is the total area in the UK where you’ll use the fertiliser, which is self-explanatory.
And lastly, what differentiates a liquid fertiliser rate from other rates is that you’ll also need to know the material’s density or weight. The formula is applicable only if you’re using a liquid fertiliser. Understanding these four values will help you apply the formula and calculate it without issues.
Step #2. Apply the formula
To further help you understand the formula, let us use an example of calculating the liquid nitrogen fertiliser rate for a crop like corn. Using the formula, you will find the N application rate in gallons per acre and the amount you’ll need to apply 160 pounds of N on the area. You will need the values mentioned earlier, which means you should be aware that a 30% UAN liquid N fertiliser will suffice for 500 acres of corn.
In this example, 10.86 pounds per gallon of fertiliser contains 30% nitrogen, which means you’ll get 0.30 pounds of N per pound of the fertiliser. One can simplify the calculation as 10.86 pounds per gallon multiplied by 0.30-pound Nitrogen per pound of fertiliser, and you’ll get the pound of N per gallon of fertiliser.
You will also get the gallon of UAN per acre by dividing 160 by the amount you’ve had previously. Using the values from the previous two computations, you can get the tons for 500 acres. Overall, the calculation for liquid fertiliser rate is similar to how you’d compute the rate of dry fertilisers.
Still, you’ll also account for the liquid fertiliser’s weight to find out its nutrient content.
If you’re still confused with using and applying the formula, a simplified equation would be multiplying the required nutrient application rate by 100 and dividing it by the per cent nutrient in the fertiliser multiplied by the fertiliser weight. Let’s say that you need to apply 15 pounds of nitrogen using a liquid fertiliser with 30% nitrogen per weight, and the weight of UAN is 10.86 pounds per gallon. How can you use the formula?
You’ll get the fertiliser rate first, which means multiplying 15 by 100 and dividing it by 30. You’ll then get 50 pounds, and you’ll divide this by 10.86. Therefore, you will need 4.6 gallons of liquid fertiliser.
How To Calculate Nutrient Requirements
Besides the liquid fertilizer rate, you also want to know how to calculate the nutrient requirements. Remember that you will only get the fertiliser’s correct rate if you see the crop nutrient requirements. Therefore, do a soil test first to ensure that you’ll meet the goals of your British garden’s productivity.
Remember that over time, the nutrients in the soil gets depleted. Some nutrients require a yearly application, while others require more frequent addition. An annual application of phosphorus and potassium should suffice, but nitrogen might be more periodic.
If you’re growing in the greenhouse, you also need to adjust the amounts because UK experts commonly recommend the fertiliser for large areas. You don’t want to guess the amounts due to the risk of over-fertilizing and under-fertilizing. You can use a simple equation of pounds recommended per 1000 square feet multiplied by square footage divided by 1000 square feet.
Knowing and calculating fertiliser rates is crucial to avoid over-fertilizing and under-fertilizing. You can learn how to calculate liquid fertilizer rates by understanding the formula and how to apply the values. While it can be daunting to see how lengthy the formula is, it’s straightforward.
One can simplify it into the required nutrient application rate multiplied by 100 and divided by the per cent nutrient in fertiliser multiplied by the fertiliser weight. You’ll be taking the liquid fertiliser’s weight into account because this pertains to its nutrient content. Additionally, don’t forget the importance of soil test before calculations because it will ensure your plants’ fertiliser needs and avoid problems.
With a proper understanding of the values and the formula itself, you should be able to calculate the rate of your liquid fertiliser without confusion. You can check out different examples from UK university extensions as well.