Fall-Applied Phosphorus: Efficient And Effective

Is fall a good time to apply phosphorus, and will the applied phosphorus be available for spring-planted crops? Those are key questions many retailers and growers ask when considering fall-applied phosphorus.

This was the subject of CropLife Media Group’s recent Webinar “Fall-Applied Phosphorus: Efficient And Effective,” presented by Dr. Barney Gordon, agronomic consultant and Professor Emeritus, Kansas State Uni­versity, and Jake Sanders, Special­ty Fertilizer Products’ (SFP) vice president of market development. The two speakers discussed the advantages and benefits of fall phosphorus application, as well as some innovative tools that help increase its availability to spring-planted crops.

Maximizing Yields With Phosphorus

Phosphorus (P) is essential for crop growth and development, Gordon said during the Webinar. “Availability of adequate P, especially early in the growing season, has a profound effect on crop yield in both corn and wheat,” he said.

While application of P to the soil is necessary to ensure plant productivity, the recovery of applied P by the crop plants is often low due to a lack of P movement, or diffusion. Gordon said there are several factors that affect phosphorus diffusion in the soil. They are:

  • Volumetric water content: Increasing soil moisture level increases rate of diffusion.
  • Soil bulk density: Changing bulk density affects the ability of nutrients to diffuse to the root surface.
  • Soil buffering capacity: Ability of the soil to maintain nutrient concentration.
  • Nutrient concentration: Initial amounts of nutrients in the soil.
  • Temperature: Increasing the temperature increases concentration in the solution.

Studies show when soil temperature is reduced from 70°F to 58°F, corn root growth decreased five-fold and P uptake by corn roots decreased four-fold, Gordon said. “The colder the soil, the more problems we have getting phosphorus to the plant,” he said.

Gordon said he’s found little difference in yield when P was applied in the fall or the spring, providing growers with much-needed flexibility.

“Weather can cause delays in the spring, which makes it difficult to get planting done in a timely manner,” he said. “Fall application of fertilizer has the advantage of taking some of the workload off of producers. We could put our fertilizer on in the fall and still have it available and working for us in the spring.”

In addition to corn, wheat also tends to be highly responsive to P input, Gordon said. “P is generally the second most limiting nutrient in wheat production, behind N (nitrogen),” he said. “And in some areas, P is more limiting than N.”

Early-season P deficiency limits yield potential in wheat production, Gordon added. “The most critical period is that first five to six weeks after emergence in the fall,” he said. “P has major impacts on tillering and rooting. So it’s critical we have adequate amounts of phosphorus in the fall when the wheat crop first germinates and starts growing.”

Greater Efficiency With AVAIL

One of the most significant problems associated with P is that it is extremely inefficient, SFP’s Sanders said. “It becomes tied-up, or fixed to the soil,” he said. “This happens because phosphorus has a negative charge and other elements in the soil have a positive charge. When they are active in the soil, they come together like a magnet and severely limit the crop’s access to the nutrient.”

Research shows that 75% to 95% of applied P is lost during the season of application. “In the best-case scenario, we are losing 75% of our phosphorus, which is an incredibly inefficient way to do business,” Sanders said. “We firmly believe that a solution to that problem is AVAIL.”
AVAIL P fertilizer enhancer is a water-soluble polymer with a very high negative charge, Sanders said. When that polymer is used as a coating on granular P or mixed into fluid P fertilizers, it diffuses out in the soil and interfaces with those positive charges that would typically tie up the P.
“Now instead of losing 75% to 95%, we keep a majority of that phosphorus available to the crop,” he said.

Sanders shared results from several corn yield studies that examined fall application of P with and without AVAIL. “We’re seeing the same positive effect whether we apply phosphorus with AVAIL in the fall or in the spring,” he said. “And when we’re talking about time savings, that’s a big deal. We can save a lot of time by getting that phosphate out early, protecting it, making it available to the crop and receiving the greatest return on investment for the grower.” 

Leave a Reply

Fertilizer Stories

Aerial view of the West Fertilizer explosion site
FertilizerFertilizer Companies Blame City For West, TX, Explosion
August 6, 2014
El Dorado Chemical Co. and CF Industries contend the city failed to properly train the first responders and had insufficient protocols in place to battle the April 17, 2013, blaze at West Fertilizer Co. that triggered the explosion. Read More
FertilizerThe Fertilizer Institute: New President, Renewed Energy
February 3, 2014
Chris Jahn relishes the opportunity to lead the organization through the challenging times ahead. Read More
FertilizerA New Cycle For Fertilizer Demand
January 2, 2014
Changes in the corn market could have a major impact on the crop nutrients sector in 2014, say experts. Read More
FertilizerOSHA Hammers West Fertilizer With Over $100K In Fines For April Explosion
October 10, 2013
The Occupational Safety and Health Administration is fining the parent company of the West Fertilizer plant, Adair Grain Inc., $118,300 for 24 violations. Read More

Trending Articles

MAGIE 2014 ShowStopper
EquipmentJohn Deere Again Wins MAGIE ShowStopper Award
August 25, 2014
For the second consecutive year, John Deere was honored at the Midwest AG Industries Exposition (MAGIE) for its new R4045 sprayer. Read More
ManagementExpert To Discuss Farmland Value, Rent At Farm Science Review
August 18, 2014
While cropland values in Ohio increased in the past two years, they have remained flat in 2014, declining in some cases, according to an Ohio State University agricultural economist. Read More
EquipmentAdvance Your Technology IQ At MAGIE
August 13, 2014
The Midwest AG Industries Exposition (August 20-21) is the place you need to be to see, study and evaluate how new advances in the equipment, operations, crop protection and fertility sectors can help your business prosper. Read More
HerbicidesScouting Key To Next Season’s Soybean Herbicide Program
August 12, 2014
When growing soybeans, growers need to think ahead to stay one step ahead of weeds. That means examining weed threats and evaluating which herbicides work best. Read More
StewardshipMichigan Agriculture Leaders On Toledo Water Ban: We Want To Be Part Of The Conversation
August 8, 2014
Leaders of Michigan agricultural organizations said Thursday that the government should not have a “knee-jerk reaction” based on last weekend’s water ban in Toledo due to fertilizer run-off in Lake Erie. Read More
CropLife 100BRANDT Acquires Lemon Ag Services
August 4, 2014
The acquisition of Lemon Ag fits BRANDT’s aggressive corporate strategy of providing superior agronomic advice and services for customers in central Illinois. Read More

Latest News

WebinarsWebinars On Demand
September 2, 2014
Register for one of our upcoming Webinars or access our archive of past Webinars to view recordings of presentations that may be of interest to you. Read More
CropLife 100Pinnacle Launches Performance Agriculture Brand
September 2, 2014
Performance Agriculture complements Pinnacle’s existing brands, including Sanders, the company’s flagship farm input retail brand. Read More
Webinars5 Key Benefits Of Attending A Webinar
September 2, 2014
Webinars can provide ag retailers with a convenient option for gaining knowledge on the latest industry issues and solutions. Read More
Crop InputsBASF Is Betting On A Bright Agricultural Future
September 1, 2014
The crop protection products giant is gearing up for a busy time in agriculture by investing in both product production and development over the next couple of years. Read More
Eric SfiligojAn Erie Feeling For Ag
September 1, 2014
Plenty of water issues have been in the news lately, including the continuing drought in California. Read More
CropLife 100Pinnacle Acquires California-Based Retailer
August 29, 2014
Pinnacle Agriculture Holdings will acquire Kerman Ag Resources, Inc., which will operate under Pinnacle's Performance Agriculture brand. Read More
Allied Cooperative Grain Plant
ManagementArcadia Co-op To Merge With Allied Cooperative
August 28, 2014
Allied Cooperative has announced that members of Arcadia Co-op voted in favor of a merger with Allied Cooperative, paving the way for the consolidation which will be effective on December 1, 2014. Read More
InsecticidesBioinsecticide VENERATE Now Registered In California
August 27, 2014
Marrone Bio Innovations' VENERATE is a new tool to help California growers control crop-damaging insect pests, fight the development of insect resistance and reduce pesticide residues on fruits and vegetables. Read More
CropLife 100Two Iowa-Based Ag Co-ops To Merge
August 27, 2014
The Board of Directors and management of United Western Coop, Missouri Valley, IA has completed a merger with Heartland Co-op, West Des Moines, IA, effective September 1, 2014. Read More
FertilizerKoch Expands AGROTAIN Nitrogen Stabilizer Portfolio
August 26, 2014
Koch Agronomic Services, LLC has added two new innovative nitrogen stabilizers to the AGROTAIN product family – AGROTAIN ADVANCED and AGROTAIN DRI-­MAXX. Read More
Seed/BiotechDuPont To Build Two Seed Treatment Centers
August 26, 2014
DuPont has announced construction on two state-of-the-art centers dedicated to developing and testing seed treatment formulations, applications and seed handling techniques in an important step toward bringing new solutions to growers. Read More
Seed/BiotechLoveland Products Acquires A Controlling Interest In Ag…
August 26, 2014
Loveland Products, a subsidiary of Agrium , has announced the company has acquired a controlling interest in Agricen, a Dallas-area agricultural biotechnology company delivering biochemical-based products for efficient and sustainable plant nutrition. Read More
StewardshipUp Close Look At The 2014 Environmental Respect Award W…
August 25, 2014
The 2014 Environmental Respect Award winners were honored recently at the 24th annual event in Wilmington, DE. Read More
Eric SfiligojAg Science Rejection Carries Consequences
August 25, 2014
As innuendo and fear dog the regulatory process, agriculture can’t get the new tools it needs to combat world hunger. Read More
LegislationFarmers Dismayed As New Farm Bill Dumps Direct Payments
August 25, 2014
The threatened end of cash subsidies to the nation’s row crop farmers dates back through at least the last two iterations of national agriculture policy legislation. Read More
MAGIE 2014 ShowStopper
EquipmentJohn Deere Again Wins MAGIE ShowStopper Award
August 25, 2014
For the second consecutive year, John Deere was honored at the Midwest AG Industries Exposition (MAGIE) for its new R4045 sprayer. Read More
CropLife 100GROWMARK CEO To Retire
August 22, 2014
GROWMARK chief executive officer Jeff Solberg has announced his retirement effective September 15, 2014. Read More
InsecticidesDuPont’s Prevathon Approved For Dry Beans
August 22, 2014
DuPont Prevathon insect control powered by Rynaxypyr has received EPA registration for foliar use on dry bean crops, including dried shelled peas and beans. Read More