It’s a no-brainer to state that liming materials improve the performance of fertilizer ingredients, particularly phosphorus and nitrogen. Now combine that certainty with the uncertainty of global fertilizer ingredient price volatility. We can assume that using one input (lime) that’s inflated 30% price-wise in the last three years to increase the utilization of ingredients – whose costs have almost doubled in that time – is a good business move.
I use anhydrous ammonia as an example of these runaway costs. This compound (whose costs are strongly tied to the market value of natural gas) was priced at $750/ton (FOB New Orleans, LA) in November 2021. During November 2022, however, the same plant food priced at $1,040/ton!
With huge geo-political uncertainty in the world (particularly relating to fertilizer ingredient costs), not liming when soil tests indicate the need to do so is a bad idea. Lest we forget, costs of anhydrous ammonia and urea (primary N sources) relate directly to the natural gas cost. And costs of the primary conventional (non-organic) P sources (mono-ammonium phosphate and di-ammonium phosphate) are indirectly linked to natural gas costs.
Not surprisingly, failure to soil test, to determine whether or not lime is needed, is just as bad an idea. With soil pH of 7.0, N utilization is 100% – a figure which is halved when pH plunges into the low fives. When soil testing, use a lab that gives base saturation percentages (BSPs). A BSP of less than 10% for magnesium will indicate the need for a dolomitic (hi-mag) lime rather than hi-cal lime. BSP is also necessary to determine the balance existing between different soil nutrients.
In good news, we learned that anhydrous ammonia cost (FOB NOLA) dropped to an average of $790/ton (per the Feb. 2, 2023 Argus North American Newsletter). Some folks believe that if fertilizer price drops a fair amount, reduced efficiency of soil amendment utilization (associated with lowered pH) is an acceptable trade-off.
Folks in that mindset likely forget the benefit of lime as a generous provider of the nutrients calcium and Mg, in addition to its trait as a pH regulator. Plant nutrients, once rendered unavailable, by whatever cause, are just as useless to the targeted plants, whether they cost $500/ton or $1,000/ton. I refer to my own crop nutrient availability demonstration, conducted during my service as a field crops Extension agent in the mid-1970s.
Working with a cooperating farmer in Otsego County, NY, I divided a gently sloping upland field into three equal parcels. Soil test results recommended four tons of 70% ENV (effective neutralizing value) hi-cal lime per acre. (The pH was in the mid-fives.) A commercial fertilizer blend of 300 lbs./acre of 15-15-15 analysis would take care of the N, phosphate and potash needs. The local farmer-owned co-op donated lime and fertilizer.
Working with Professor Shaw Reid at Cornell’s Agronomy Department, I followed his recommendations to vary the lime application rate. He told me that if I applied half the recommended lime rate on a corn planting, I could expect 75% of the yield increase associated with full lime application. One parcel received 4 tons/acre of lime, one parcel received 2 tons/acre of lime and one parcel received zero lime.
The corn piece with zero fertilizer yielded 11 tons/acre of 35% dry matter (DM) silage. The two-ton lime recipient yielded 17 tons silage/acre and the 4-ton recipient yielded 19 tons silage/acre. According to my math, Shaw’s yield forecast was spot on. He did caution me that the short-changed corn parcels should get the rest of what they were owed lime-wise in the next couple years.
On Feb. 28, 2023, I received an online news release from The Fertilizer Institute (TFI). It stated that TFI’s CEO Corey Rosenbusch had just provided official testimony during the House Ag Committee’s hearing which dealt with uncertainty, inflation and regulations. Quoting from Rosenbusch’s topic: “‘Challenges for American Agriculture’: Fertilizer is an essential tool for farmers to achieve the yields necessary to feed our growing world. We appreciate the opportunity to shed light on current market dynamics and offer solutions to the pressures currently facing the U.S. agricultural sector. As always, the fertilizer industry is committed to ensuring adequate supply to meet farmer demand for the nutrients that are so essential to growing healthy and abundant crops.”
He tailored much of his testimony to the fact that fertilizer is a globally traded commodity subject to international pressures and geopolitical events. He stated that domestic production of fertilizer accounts for only 7% of global production, and that 90% of all fertilizer consumption happens outside our borders. This statement supports Farm Bureau data showing that while in 1960 American farmers consumed 25% of the world’s fertilizer, that figure by 2020 had dropped to only 10%. This means that global production has intensified so much that at any given moment somebody, somewhere, is planting something.
Rosenbusch continued, “Geopolitical events have been the biggest disrupter to fertilizer markets in recent years.” The events to which he referred included sanctions on Belarus, which supplies 20% of the world’s potash supply. There’s China, a major exporter of fertilizers, which last year imposed restrictions on fertilizer exports, and Russia, which has historically met 20% of global fertilizer supplies as the world’s largest fertilizer exporter.
Rosenbusch then offered solutions and items Congress could act on to improve domestic production and supply: “While Congress cannot control Russia and China, there are a number of areas where policy could have a positive impact on the agricultural sector. Regulatory certainty is perhaps the most significant area Congress could help.”
He also cited the need for our powers-that-be to list potash and phosphate as critical minerals, and to support energy policies that promote an abundant, affordable supply of natural gas, thus streamlining long delayed fertilizer projects. Conspicuously absent from Rosenbusch’s testimony was any mention of ground limestone, which, to date, has managed to avoid the spotlight on the international crop input commodity stage.