Renewable Farming

Your high-clearance sprayer can make you extra money in midsummer

We were stunned to learn from Darrell Bruggink of No-Till Farmer that only 20% of their subscribers with 1,000 acres or more do any foliar feeding of nutrients. 

Many of them have high-clearance sprayers — but they typically park those amazing rigs in the machine shed after spraying herbicides and maybe some fungicide. Spraying nutrients late in the season is a “next frontier” for higher yields. That’s evident among the corn yield contest winners, who routinely apply foliar nutrients through the season, as sap tests or tissue tests indicate.

At an AgriEnergy Resources seminar earlier this year, I asked the 300-plus farmers in the audience, “Raise your hand if you do any foliar feeding.” About three out of four farmers raised their hands. Foliars have been a definite part of the AgriEnergy Resources biological nutrition program for three decades. Today’s large, fast, GPS spray rigs with precision controls offer a huge advantage for foliar programs. So does sap testing and rapid-response tissue testing. 

We’ve spent more than eight years demonstrating that about 5 ounces of WakeUP in the foliar-feeding tank mix sharply improves foliar nutrient absorption and metabolism. Generally if a good foliar improves yields 5 bushels, including WakeUP Summer will add another 4 bushels of yield for a total of 9 bushels. Even with $3 corn, the additional revenue of $12 is a very positive return on the WakeUP cost of about $3.50 per acre for 5 ounces. The positive aspect of owning your own sprayer is that you don’t have to add a cash outlay for custom spraying. There are other advantages, such as controlling the timing for applying foliar fertility:  Early morning and late evening are best, in the cool and quiet of the day.  OK if there’s some dew on the leaves; that enhances nutrient absorption and “spreading” of spray application on the leaves.

You don’t need an expensive, GPS high-clearance sprayer for foliar nutrient applications. The tolerance for variation in application rates is generous. So a well-calibrated, older sprayer will work well. We have two old Hagies for our experimental work and they do the job.

AgriEnergy’s Ken Musselman posted a convincing rationale for summer foliar feeding on the AgriEnergy site July 27.  It’s at this link:

Here’s just part of Ken’s foliar-feedine encouragement, which you’ll see on the AgriEnergy site:

We want to make sure that plants have enough nutrients and energy to keep directing starches and proteins to the seed.  Many nutrients come into play here.  We need:

  • Magnesium for chlorophyll formation to make sure we are making the most of photosynthetic potential
  • Boron to help move sugars within the plant
  • Nitrogen and sulfur for protein formation
  • Potassium to help with sizing the seed
  • And, a constant supply of phosphorus to keep the energy cycling in the plant

All these nutrients affect the hormone balance of the plant and therefore how the plant uses energy.  Some of our biggest foliar responses have come in the last 30 days before maturity as a result of providing the plant with some of these vital nutrients at a critical time.

Another rationale for late-season foliar applications comes from David Miller, VP for agronomy education at Advancing Eco Agriculture. Instead of depending on fungicides for late disease control, Miller encourages foliar nutrition to ease the stress that crops go through when yield is being built.  Several of our neighbors here in northeast Iowa call in the spray planes in early August, because they’ve seen some benefit in fighting mid-season diseases which look like they’re fungi-related.    Click here for a link to Miller’s article.


Published July 28, 2016 by Jerry Carlson