Unveiling Innovations: Liqui-Grow L.E.A.D. Academy Webinar November 30th!


The Liqui-Grow L.E.A.D. Academy is back in session on November 30th. Dr. Jake Vosennkemper will be diving into the latest research and insights that are shaping the future of farming.

Agenda Highlights:

ExactStrip Distance Study:

Jake shares his findings from this year’s ExactStrip Distance Study to discover how close your nutrients need to be applied to achieve the best results!

Multi-Location Fertilizer Placement Study:

Uncover the secrets of effective fertilizer placement through a comprehensive study conducted across multiple locations. Discover the best practices that can enhance nutrient uptake and contribute to healthier crops.

In-Furrow Additives for Corn:

Stay at the forefront of corn production with the latest updates on in-furrow additives as Dr. Jake explores how these additives ultimately increase your crop yields.

Multi-Location Foliar Applied Biological Screening Study in Soybeans:

Dr. Jake takes a deep dive into how new technologies and management strategies play a key role in improving soybean performance and yield.

The Importance of Including Zn in Starter Fertilizer:

Witness the impact of zinc (Zn) in starter fertilizers through a compelling real-world example. Learn why including this essential micronutrient is a game-changer for crop development and yield optimization.

Don't miss this opportunity to learn new strategies for your operation. Join the Liqui-Grow L.E.A.D. Academy Webinar on November 30th, and empower yourself with the knowledge to elevate your farming practices. 

Register TODAY!


Questions? Give us a shout! 

Text us at 564-220-2508 or email questions@liqui-grow.com.

How to Achieve Consistent Fertilizer Applications With Every Pass


Technology has given every grower the opportunity to precisely manage input costs and achieve maximum yield potential. When it comes to fertilizer applications, though, most farmers just throw nutrients on the field and hope the plant gets the benefit. 

Flat rate dry fertilizer application is a perfect example of this. Growers using this method spread a flat rate of nitrogen, potassium and phosphorus on their field each year to keep nutrients available in the soil and increase yield potential. However, flat rate application fails to account for nutrient differences across the field and assumes that every acre needs the same amount of fertilizer each year.

To provide more accuracy and reduce cost, many growers shifted to using variable rate application methods. Based on annual soil sample results, growers could have custom recommendations for every field they sampled and calculate exactly how much of each fertilizer they needed each year. This allowed growers to save on input costs while providing the nutrients necessary to hit desired yield goals.

Unfortunately, the problem wasn’t fully solved.

Research has revealed that each type of dry fertilizer has a different spread pattern. This means even with a variable rate application, some nutrients are still spread heavier or lighter than desired. 

A 2018 Iowa State University study also found that dry fertilizer spreaders often have uneven distribution across their swath, even with proper calibration. The study showed that across a normal 90-120 foot spread pattern, the application directly behind the machine was less than on each side. The lack of consistent application results in fertilizer granules being scattered across the ground, oftentimes too far from the plant roots to be easily absorbed. 


The good news is Liqui-Grow has a solution.

The Liqui-Grow Advantage

Rather than spreading dry fertilizer that has to be dissolved and broken down to be absorbed, we start with liquid fertilizer. Liquid P & K Suspensions provide equal amounts of liquid fertilizer evenly across every acre. 

Why does this matter?

Our standard liquid suspension is applied in 15” centered rows, which we call banding.  Placing highly concentrated nutrients in close proximity to the plant improves uptake and utilization. Because the fertilizer is already in liquid form, it doesn’t get bound up in the soil, or by other nutrients like Calcium, Iron and Aluminum. This allows the plant to absorb it quicker than dry fertilizer. Learn more about banding fertilizer here.

Arguably the biggest benefit of liquid suspension fertilizer, though, is the increased performance in the field and profit potential. 

In our field trials of dry and liquid fertilizer application, we tested both flat fields and farms with hillsides to compare uniformity and harvest results. Not only did liquid suspension fertilizer provide a more even application with every pass, the dry fertilizer application resulted in higher levels of inconsistency as the rate increased, or when applied on a hillside.

This result is a leading cause for the multiple issues we see in fields with nutrient deficiencies, and it means growers are not receiving the full benefit from their investment. When the floater drives across your field, you should be confident every plant on every acre receives the nutrients it needs to perform.  

More efficient application always results in more profit potential. That’s why liquid fertilizer was developed. In fact, our research has shown that applying a liquid suspension band can result in five bushel per acre yield increase compared to broadcast applications. That’s money back in your pocket every time!

To feed your crop evenly, improve your field performance and profit potential, text us at 564-220-2508 or email questions@liqui-grow.com.

New Research Comparing Ortho/Poly-Phosphate Ratios


Blog Banner for Poly Phosphate study


  • Ortho-phosphates are 100% plant available, but a high percentage of poly-phosphates in starter fertilizers convert to ortho-phosphate within just two days after application.
  • This quick conversion from poly to ortho-phosphate suggests expensive “high” ortho starter fertilizers are not likely to result in increased corn yields compared to conventional poly-phosphate starters.
  • On-farm field studies conducted near Traer, IA and Walnut, IL from the 2016 to 2018 growing season found no statistical difference (Pr > 0.05) in corn yield between conventional and high ortho-phosphate starters.
  • High ortho starters cost more per/ac than conventional poly-phosphate starters, but do not increase corn grain yields.

Poly-phosphates Rapidly Convert to Plant available Ortho-Phosphates

Given poly-phosphates are not immediately plant available and ortho-phosphates are immediately plant available, this gives the promoters of “high” ortho-phosphate starters ample opportunity to muddy the waters. Nevertheless, the facts are, poly-phosphates are rather rapidly hydrolyzed (converted to) into ortho-phosphates once applied to soils, and this hydrolysis process generally takes just 48 hrs or so to complete.

In Sept of 2015 I posted a blog discussing some of the more technical reasons why the ratio of ortho- to poly-phosphates in starter fertilizers should have no impact on corn yields. For those that are interested in the more technical details, I encourage you to follow this link to
the Sept 2015 blog post (liqui-grow.com/farm-journal).

While we were relatively certain that the ratio of ortho to poly-phosphates in liquid starters should have no effect
on corn yields, I decide to “test” this idea with on-farm field trials located near Traer, IA and Walnut, IL  in the 2016, 2017 and 2018 growing seasons.

tractor planting fertilizer

Picture 1. Planting starter fertilizer trials near Traer, IA in the growing season of 2016.


How the Field Trial Was Conducted

In these field trials we used two starters applied in-furrow at 6 gal/ac. Each starter had a NPK nutrient analysis of 6-24-6. The only difference between these two starters was the ratio of ortho to poly-phosphates. One of these starters contained 80% ortho-phosphate and the other contained just 50% ortho-phosphate. With the remainder of the phosphorous source in each of these two starters being poly-phosphate. At the Traer, IA locations the plots were planted with a 24-row planter (picture 1) and were nearly 2400ft long. At the walnut, IL locations the research was conducted using small plot techniques, plot dimensions there were 10 ft wide by 30 ft long. At both Traer, IA and Walnut, IL in each of the 3 growing season the experimental design used was a simple randomized complete block with 4 or 5 replications.

Figure 1. Average corn yield from field trials comparing high ortho vs conventional poly-phosphate in-furrow seed safe starter fertilizers. Yields at each location/year are averaged over 4 or 5 replications.


Figure 2. Partial profit from field trials comparing high ortho vs conventional poly-phosphate in-furrow seed safe starter fertilizers. Yields at each location/year are averaged over 4 or 5 replications. Partial profit was calculated using a grain sale price of 3.50 bu. Cost per gal used to calculate partial profit for the 6-24-6 50% ortho & 50% poly-phosphate and 6-24-6 80% ortho & 20% poly-phosphate was $2.80 and 3.20 per/gal


Field Trial Results

Averaged over the 5 site-years there was only about 1.5 bu/ac yield difference separating the high ortho and conventional poly-phosphate starter (figure 1). Moreover, this small yield difference was not statistically significant (Pr > 0.05). In addition to finding no differences in grain yield between these two starters, the high ortho starter cost about $0.50 more per/gal (so $3/ac difference in price at a 6 gal/ac rate) than the lower ortho starters. So the more expensive high ortho starter clearly did not “pay” its way in our multi-location field trials (figure 2). Lastly, our observations in these studies agree with previously published university findings (Frazen and Gerwing. 1997).


Franzen D. and J. Gerwing. 2007. Effectiveness of using low rates of plant nutrients. North Central regional research publication No. 341. http://www.extension.umn.edu/agriculture/nutrient-management/fertilizer-management/docs/Feb-97-1.pdf (accessed 8 of Sept 2015).


– Dr. Jacob Vossenkemper (Agronomy Research Lead)

Urea – A Poor Choice of Nitrogen Fertilizer for In-Season N Applications

John Deere tractor in corn field



  • Urea fertilizer, if not incorporated by tillage or precipitation, is highly susceptible to ammonia volatilization (loss to the atmosphere as ammonia gas).
  • Uniform application of urea can be problematic due to segregation of larger and smaller urea prills and due to physical spread pattern interference from standing corn during in-season applications.
  • Liquid UAN (32 or 28%) is only 50% urea and is about half has susceptible to ammonia volatilization as dry urea.
  • Banding UAN further reduces the probability of nitrogen loss via ammonia volatilization.
  • Averaged over 3 on-farm plots side-dressing surface banded UAN gave 16.2 $/ac greater net returns and yielded 5.5 bu/ac more than surface broadcasted urea.

Urea, anhydrous ammonia and liquid urea ammonium nitrate (UAN 28 or 32%) are by far the most common sources of nitrogen fertilizer used in corn production. Moreover, all 3 sources of nitrogen fertilizer have their own unique advantages and disadvantages, but in particular, dry urea is an exceptionally poor source of nitrogen for in-season applications to corn. At first glance, urea seems to be an attractive in-season nitrogen source, because it can be applied rapidly with high clearance dry spinner spreaders and urea is commonly a few cents per lb of nitrogen cheaper than UAN. Urea, however, is highly susceptible to N loss via ammonia volatilization and uniform fertilizer nitrogen distribution can be a serious problem for top yields and maximizing economic returns.

Dry Urea: Elevated Risk for N Loss via Ammonia

Ammonia volatilization occurs when the urease enzyme hydrolyzes urea fertilizer to ammonia on the soil surface. Given ammonia (NH3) is a gas and lighter than air, the ammonia literally floats away into the atmosphere. The most effective way to prevent ammonia volatilization is for urea hydrolysis to occur beneath the soil surface where the ammonia gas can interact with hydrogen ions to form ammonium (NH4+).

To avoid serious N loss, urea must be incorporated with tillage, moved below the soil surface by precipitation or subsurface injected. For in-season N application, however, physical incorporation or injection of dry urea is not practical, leaving a rainfall event that must exceed 0.5 inches to move the urea below the soil surface (figure 1). This significant rainfall event must occur no later than 4 days after urea application (figure 2) or N loss from ammonia volatilization could drastically accelerate in subsequent days (Jones et al., 2013). UAN is also susceptible to ammonia volatilization, but only 50% of the nitrogen in UAN is urea. Therefore, UAN is roughly half as susceptible to ammonia volatilization as dry urea.

irrigation rate graph

UAN also provides more flexibility regarding in-season applications than dry urea. UAN can be subsurface injected or surface banded within the row. Subsurface injection of UAN strongly reduces the potential for ammonia volatilization because urea hydrolyses occurs below the soil surface. Banding UAN on the soil surface does not eliminate ammonia volatilization, but reduces the risk of ammonia volatilization considerably (figure 2, Jones et al., 2013). The reduction in ammonia volatilization risk with banding UAN occurs because banding physically reduces the amount of N fertilizer exposed to the urease enzyme.

Field with low Urea rate stripes

Poor Fertilization: Increases Yield Loss Risk

Achieving uniform application with dry fertilizer, which includes urea, can be a difficult task. Several problems exist that can lead to non-uniform urea applications. If urea is not uniformly sized, the result is segregation of larger and smaller urea particles during loading, transportation to the field and during spreading. Particle segregation is a problem because larger urea granules are thrown further from the dry spinner spreader machine than smaller particles, resulting in a higher application rate directly behind the machine and a lower applications rate at the edges of each pass.

Segregation is not the only concern. When side-dressing corn, poor urea distribution can be exacerbated by the standing corn crop, particularly when corn reaches over a few feet in height. Tall corn acts as a funnel, cutting down the distance at which the urea granules can be thrown compared to when no crop was present to disrupt the flow of urea toward the edges of each pass.

On-Farm comparisons: Broadcast Urea vs. Surface Banded UAN as In-Season N Sources

The on-farm studies were conducted at 3 locations in the 2016 growing season. The locations included Elkhorn, WI, Tipton and Morning Sun, IA. The base and side-dress N rates used at each location are listed in table 1. At each location the side-dress nitrogen was applied at growth stages between V6 to V8 as either surface banded UAN or surface broadcasted urea. At each location these treatments were replicated 3 or 4 times. The price of UAN and urea used to calculate partial profit was 0.36 and 0.32 $/lb N. The price of corn used to calculate partial profit was 3.50/bu.

Surface Banded UAN vs Surface Broadcasted Urea chart

Averaged over the 3 locations yields were increased 5.5 bu/ac from surface banded UAN when compared to surface broadcast urea (table 2 and figure 3). In addition to higher yields from surface banding UAN vs broadcasting urea, net profits were 16.2 $/ac higher for the surface banded UAN treatments, despite slightly higher nitrogen costs (table 3).

Table 1table 2table 3


Because urea cannot be physically incorporating post-planting, it is susceptible to loss via ammonia volatilization (loss to the atmosphere as NH3 gas). Moreover, uniform application with dry fertilizer, including urea, can be problematic due to segregation of larger and smaller urea prills and due to physical spread pattern interference from standing corn. For these reasons, urea is a particularly poor source of nitrogen fertilizer for in-season applications. In these 3 on-farm trials surface banding UAN increased yields 5.5 bu/ac and net profits 16.2 $/ac compared to surface broadcasting dry urea.


Jones, C., B.D. Brown, R. Horneck, D. Olson-Rutz. 2013. Management to Minimize Nitrogen Fertilizer Volatilization. Extension Publication EB0209. Montana State University. http://www.landresources.montana.edu /soilfertility/documents/PDF/pub/UvolBMPEB0209.pdf.


– Dr. Jacob Vossenkemper (Agronomy Research Lead)