The more you know about your soil, the better enabled you will be to make fertilizer decisions that work on every area of your farm

While harvest brings the 2023 growing season to a close, preparation for next year is already underway. 

Pat Kunz has signed up to have his soil tested across all his fields in anticipation of making informed fertilizer purchases for the upcoming spring. He says monitoring soil health has become an important step to make the most out of existing soil moisture and how he applies fertilizer.

“Managing soil health allows us to replenish our soil nutrients and be more accurate in the way in which we do it,” he says. “What we do with those soil testing results depends on the year and what is in our rotation. I have zero doubt that it is an important tool for us, that it is improving organic matter and it is increasing yield.”

Kunz owns a mixed farm outside of Beiseker, Alberta. He was an early adopter of combining close monitoring of soil health with variable rate fertilizer application technology. He was involved in proof-of-concept trials in the late 2000s and has included it in his practices ever since. 

“I grew up on this land and I want to be able to leave it to my four kids in as good a shape as possible,” he says. “That means maintaining everything, from the equipment to the cattle pens to the health of the soil. Variable rate application is one piece of the puzzle, an important piece that I don’t see myself getting away from as it has had a positive impact on where we use fertilizer and on how much we use.”

Know what’s in your soil for a better fertilizer plan

Healthy, nutrient-dense soils help to grow productive crops. As part of the commitment to supporting growers make the most informed decisions, Decisive Farming by TELUS Agriculture agronomists review soil tests and develop specific recommendations for each zone on a farm to account for variations in texture, organic matter, nutrient content, water-holding capacity and compaction – all important for crop nutrient uptake and overall crop performance.

As soon as harvest is done, the team from Decisive Farming takes samples at two or three different depths for analysis. Over the winter, Kunz meets with his agronomist to discuss his rotation. That discussion is fairly fluid and details change throughout the winter. He is then sent his prescription maps prior to seeding in April. These plug into the seeder and are ready to go. 

 “We believe in the information contained in the soil and with GPS technology in virtually every tractor on the farm, that technology is readily accessible to farmers,” says Garth Donald, manager of agronomy, Decisive Farming by TELUS Agriculture. “We can go back to the same spot every year and make sure that farmers are getting multi-year data to make informed decisions on what kind of nutrients they need to be applying on every area on their farm – in every peak and every valley as all soil is not the same so it all has different needs.”

Kunz says before he adopted variable rate (VR) fertilizer, he was blanket applying his nutrition, which he knew meant he was spending hundreds of dollars on fertilizer for areas where uptake was minimal and also not giving areas that could use extra fertility the opportunity to thrive. 

The soil’s ability to uptake and remove nutrients are at the foundation of zone management and variable rate fertility strategies. As growers manage each field according to various growth zones, they are able to reach their optimal yield potential with a tailored VR program. With Decisive Farming’s Optimize RX, regional agronomists work with farmers to develop a tailored and cost efficient plan based on each field’s unique needs.

Kunz says when he started using VR technology his goal was not necessarily to use less fertilizer, it was to apply his fertilizer in a more targeted manner. But it turned out that putting it in the right place at the right time not only delivered higher yields, it reduced overall spending and created less problems with lodging.

“On top of VR, we have incorporated additional soil health strategies,” he says. “We added peas into our rotation, which can be a challenging crop to grow in our area but help to fix nitrogen in the soil. There’s no question that switching to primarily zero till made a big difference with soil moisture. Also, we have added cover crops into our rotation which has also helped keep our soil healthy.”

Maintaining soil health for better yield potential

Donald says the 2023 growing season was one of the most challenging years for many growers on the Prairies – multiple years of drought and lower application rates as a reaction to high fertilizer prices in the previous year meant that a lot of the soil was depleted. He says in order to get a high yielding crop, it’s more important than ever to know what you are working with and then to use your nutrients accordingly.

“Growers assume that nitrogen is going to be their biggest deficiency and that is most often the case,” says Donald. “But sometimes, or in one area of their farm they need to deal with phosphorus or potassium. They won’t know this without a soil test and it can have a big impact on their overall soil health.”

Decisive Farming uses satellite imagery to determine a regular benchmark and then returns to that area every season. Instead of coming with one rate per quarter section, they do five to create a variable rate that is truly tailored to all the hills and valleys of a field. 

“By determining the health of the soil through sampling and then developing a variable rate map we can work with the grower to come up with a potential yield outcome,” he says. “Of course there are a lot of other factors that go into the season but this helps kick off a new growing season with the knowledge of what they can get from their field if they treat it right.”

Everything that the Decisive Farming recommends is sent to a grower’s device through the Farm at Hand app, so the grower has their soil testing results and their mapping recommendations in the palm of their hand. They can approve recommendations and upload them into their equipment, or work with their Decisive Farming agronomist to make any changes based on their cropping plans. 

“We believe in working together with farmers to find solutions that make their businesses work more efficiently,” Donald says. “We want to understand their goals and then come up with solutions to help them get what they are looking for. Variable rate application isn’t a flick of the switch solution, but it is a process to help improve soil health and get higher yields through improved use of farming processes. What one farmer says is a success – for example higher yields, another farmer might define it by easier harvestability through reduced lodging. Understanding what they are looking for helps us help them.”

This article was produced as part of a Soil Health series with sponsor content stories also appearing in The Globe and Mail.