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Soil testing tips for the perfect fertilizer application

No matter the crop, there is one practice that translates to them all, and that is soil testing. This ritual of profiling the soil not only helps farmers analyze their fields, but allows them to better gauge what nutrients are needed for their crops that growing season, and monitor the success of nutrient management practices.

Timing is everything

Depending on the crop and growing region, typically it is best to test your soil after harvest and before fall fertilizer applications, when it is most depleted of nutrients. Testing during this time frame will allow you to get better samples of what exact nutrients are needed on your operation. Soil tests can tell farmers the pH of the soil and the levels of potassium, phosphorus, nitrogen, calcium, magnesium and more. Knowing these levels before applying any kind of fertilizer will help save farmers money by not spreading fertilizer that isn’t needed in the fields. If you are testing annually, be sure to test around the same time every year for an accurate profile of your soil.

Tips for soil testing

Before testing your soil, make sure you know what goals you are trying to achieve. Before the use of GPS and precision agriculture, many farmers would randomly select places in the field to sample. Thanks to advanced technology, farmers are now able to assess soil health. If you don’t have access to GPS for your fields, using a zig-zag pattern across your field is suggested to ensure an accurate reflection of the field’s nutrient profile. Avoid special problem areas, such as old feedlots, homesteads, ponded areas, within 50 feet of gravel roads, or extreme soil types (which you may wish to sample separately for larger areas).

Essential tools for the job

To get started, you will need a clean bucket and a soil probe. Be sure to not use a brass, bronze or galvanized probe or container because they may contaminate the soil sample with metals; plastic containers and stainless-steel tools should be used. When you have selected your spot to test, push the probe into the soil up to 6-7 inches. A shallow sample can prove inaccurate results through topsoil and plant vegetation. Once you are satisfied with your sample, or “soil core”, and there are not any air pockets or debris, place the soil into the bucket. Repeat this process 20-40 times at random locations across a field combining all cores in the bucket and mixing thoroughly breaking clods into small particles.  Take a well-mixed subsample of this soil, label it with the name of the field, and other necessary identification, and send to the lab. Be sure to check with your lab for proper handling procedures, the proper amount of soil to send in for a sample, and shipping instructions.

Get the right nitrogen with less of the loss

ESN Smart Nitrogen provides controlled release of nitrogen to your crop over a 50-80-day period, responding to soil temperature just like your crops.

Learn more about how ESN reduces nitrogen loss here.

Be sure to contact your local ESN representative to learn more about how ESN can fit your farm.

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