Sulfur is an important nutrient to all plants, though it can be easily overlooked. Let’s take a look at how to add sulfur to corn, including the methods, amounts, fertilizer types, and research. We can see how sulfur additions to corn affect yields, and how to get the most out of sulfur fertilizers for corn. We’ve updated this blog post in 2022 to provide additional research and give you even more information.
Sulfur and Corn: Why It’s Important
As with many crop nutrients, sulfur plays a part in many plant functions. One of the primary reasons sulfur is critical to crop production is that it works hand-in-hand with nitrogen in the plant. Sulfur is required to allow the plant to use nitrogen efficiently. Poor nitrogen performance in crops is often associated with lower than optimum available sulfur.
But sulfur is a vital crop nutrient itself. It is an integral part of amino acids, which are essential for plant protein production. It also contributes to chlorophyll formation which is a key component of photosynthesis in plants. Considering what we know of the need for sulfur, and taking into account cooler environmental conditions at planting which may limit any mineralization of sulfur from the soil, we can draw the conclusion that early sulfur applications may be beneficial to the development of the young seedling. When it comes to sulfur additions to corn, let’s take a look at sulfur fertilizer at planting first.
Sulfur Additions to Corn at Planting
There are many different application methods and products available to meet the sulfur needs of corn crops. Applying sulfur with the planter is an excellent placement method to get the available form of the nutrient next to the root system and maximize the benefit to the new plant. This placement can also be more environmentally friendly because it is placed near the zone of uptake and will likely get used by the young plant before it has a chance to leach from the soil system.
Which Sulfur Fertilizer Can Be Used In-Furrow?
One of the best products to apply with the planter is AgroLiquid’s eNhance™, which can be safely applied in-furrow with common rates of 1-2 qts/A for most crops. It has been an exceptional product for providing three to six pounds of equivalent sulfur at those rates. Very few—if any—other sulfur products can be used in-furrow. This gives eNhance an edge; when applied in-furrow, it’s the closest sulfur source to the new seedling’s root system.
How Sulfur and Nitrogen Work Together
Applying nitrogen while planting also provides an opportunity to add sulfur to the nutrient program. The addition of sulfur to applied nitrogen improves the plant’s response to that nitrogen.
Nitrogen and Sulfur Additions to Corn: 2×2 Placement
One AgroLiquid product that mixes well with liquid nitrogen fertilizers is accesS. Nitrogen fertilizer is often placed 2×2 or on one or both sides of the row, the latter of which is becoming more common. These placement areas near, but not directly with the seed are still beneficial to the young root system. AccesS should only be applied away from the seed and the aforementioned systems work well for planter application of this product. A typical planter application may be 1-2 gallons per acre which would provide five to 10 pounds of equivalent sulfur.
Sulfur Additions to Corn: Dataset
At our North Central Research Station, we conduct studies on many different crops with many different fertilizer programs, so we can see the results for ourselves. We also work with other farmers and planters to solve fertilizer challenges and optimize fertilizer programs. The chart below shows data from both eNhance and accesS in multi-year studies. At least seven years of data and 12 experiments were used to compare additional planter applied sulfur to a normal planter program without sulfur.
Let’s take a look at additional research showing how sulfur additions to corn can affect yields under different conditions.
Comparing Sulfur Fertilizers and Rates
Experiment Info
| Planted | 6/1/2011 |
| Variety | DeKalb 46-07 |
| Population | 32,000 |
| Previous Crop | corn |
| Plot Size | 15′ x 225′ |
| Replications | 4 |
| Sidedress | 6/14/2011 |
| Harvested | 11/2/2011 |
Soil Test Values (ppm)
| pH | 7.1 |
| CEC | 16.5 |
| %OM | 4.7 |
| Bicarb | 11 |
| K | 132 |
| S | 8 |
| %K | 2.1 |
| %Mg | 20.1 |
| %Ca | 77.6 |
| %H | 0 |
| %Na | 0.2 |
| Zn | 1.4 |
| Mn | 2 |
| B | 0.6 |
This experiment also assessed the use of sulfur fertilizer additives, eNhance and accesS, to a corn planter program.
The first source, eNhance, is a seed safe option and can be applied in-furrow up to 3 qt/A. This experiment compared 5 gal/A Pro-Germinator and 2 qt/A Micro 500 with and without the addition of 2 qt eNhance applied in-furrow. The other source, accesS is not for in-furrow and should be applied away from the seed in a 2×2 band. This was compared to the same planter rates of Pro-Germinator and Micro 500 but applied 2×2 with and without the addition of either 2 or 4 gal/A of accesS. Yield results appear on the table below.
Conclusions:
- Highest yield was with the eNhance in-furrow applications. Next was microLink Sulfur and then accesS. This confi rms that accesS should not be applied in-furrow, even though we did not observe stand loss.
- accesS at any of the applications did not produce corn yield as high as that with eNhance, even though in other experiments it was as good as or better than ATS as a sulfur source.
- eNhance has been proven as a very good in-furrow sulfur additive for corn for several years at the NCRS.
- It was interesting to note that even though the soil sulfur level was low (8 ppm), there was no rate effect as the yields with either 1 or 2 qt/A of any of the products were similar. These results and others like it make research a challenge.
Soil Test Values (ppm)
| Planted | 5-25-2014 |
| Harvest | 10/30/2014 |
| Yield Goal | 175 bu/A |
| Target Fert. | 193-100-43 |
| Variety | DKC 49-29 RIB |
| Population | 29,500 |
| Row Width | 30″ |
| Prev. Crop | Soybeans |
| Plot Size | 15 x 265 |
| Replications | 4 |
| Sidedress | 6/30/2014 |
| pH | 6.4 |
| CEC | 13.3 |
| %OM | 2.3 |
| Bray P1 | 8 |
| Bicarb P | – |
| K | 123 |
| S | 11 |
| %K | 2.4 |
| %Mg | 16.2 |
| %Ca | 72.3 |
| %H | 8.7 |
| Zn | 1.3 |
| Mn | 8 |
| B | 0.5 |
This experiment also assessed the use of sulfur fertilizer additives, eNhance and accesS, to a corn planter program.
The first source, eNhance, is a seed safe option and can be applied in-furrow up to 3 qt/A. This experiment compared 5 gal/A Pro-Germinator and 2 qt/A Micro 500 with and without the addition of 2 qt eNhance applied in-furrow. The other source, accesS is not for in-furrow and should be applied away from the seed in a 2×2 band. This was compared to the same planter rates of Pro-Germinator and Micro 500 but applied 2×2 with and without the addition of either 2 or 4 gal/A of accesS. Yield results appear on the table below.
Conclusions:
- Both planter applied programs of Pro-Germinator and Micro 500 increased yield significantly over the no planter fertilizer check. There was a slight yield advantage, 2.7 bu/A, to applying Pro-Germinator + Micro 500 in-furrow compared to 2×2.
- The addition of 2 qt/A of eNhance to an in-furrow planter application increased corn yield by over 6 bu/A.
- Applications of accesS to a 2×2 planter fertilizer program increased corn yield nearly 2 bu/A when applied at 2 gal/A however, highest yield was achieved with the 4 gal/A rate with nearly 9 bu/A increase.
- Both eNhance and accesS are excellent sources of sulfur and can be easily added to a corn planter fertilizer
program to provide the necessary sulfur a crop needs to achieve top yield.
Adding Sulfur Fertilizer to Corn
Clearly, there are many ways to supplement sulfur and add sulfur fertilizer to corn. Which method you choose depends on your fertilizer program, soil type, environmental conditions, and more. If you have questions about how to add sulfur to corn, contact us.