• Plant Health

Fine-Tune Your Soil Fertility Plan

Farmer analyzing soil.
Just like us, crops need a well-balanced diet to optimize productivity. When just one essential nutrient is insufficient, the plant can’t carry out metabolic functions as efficiently, which could negatively impact the crop. If you’re looking for ways to fine-tune your fertility plan this season, here are some tips to help.

Balance economics and agronomics

With skyrocketing fertilizer prices, you may be looking for ways to cut your expenses without impacting your crop’s yield potential. Start with your soil test results, as they can provide a baseline for making decisions. If you’ve done a good job keeping up with fertility over the past several years, you may be able to cut back on nutrient applications this season and focus those dollars elsewhere. For example, phosphorus and potassium are immobile in the soil, so you may have banked reserves if you’ve consistently applied those nutrients. If your soil tests indicate adequate nutrient levels, you may be able to cut back or eliminate those applications without seeing much of a yield impact this season. 

Micromanage your nitrogen

With nitrogen prices at record levels, you want to put extra focus on your management plan this season. This may be a good time to experiment with new production practices or technologies that help you fine-tune your strategy.
Consider zone management
This season offers an excellent opportunity to experiment with zone management if you’re used to applying a blanket nitrogen rate across all fields. By reviewing your crop and yield history and using soil samples to guide field-by-field nitrogen plans, you’ll be able to allocate your nitrogen dollars more effectively.
Determine the optimal nitrogen rate
You never want to apply more nitrogen than your crop needs, but that’s even more critical this season with inflated fertilizer prices. Set realistic yield goals and match your nitrogen rates accordingly. Review response-to nitrogen scores for your selected hybrids to understand which fields will likely benefit from additional nitrogen.
Tissue sampling can give you a real-time snapshot of how well your crop is taking up nutrients and can help you determine whether in-season amendments are necessary. Using all these strategies can help you dial in on just the right nitrogen rate.
Stabilize nitrogen
Protect your fertility investment by using nitrogen stabilizers to keep more nitrogen in the root zone. Typically, nitrogen stabilizers are applied with the first nitrogen application, whether in the fall with anhydrous or in the spring with pre-plant applications. They limit microbial activity in the soil, reducing the conversion of ammonium into nitrate, which keeps nitrogen in a form that is less susceptible to loss by leaching or denitrification. This season, it could be beneficial to consider using nitrogen stabilizers with in-season sidedress applications to provide additional protection against nitrogen loss.
Spoon-feed your crops
A split nitrogen application is the most efficient way to feed your crop for two reasons. First, it limits loss by leaching and denitrification, especially in areas where wet springs are the norm. Second, when you can time applications closer to peak nitrogen uptake, the application will be more effective. Sidedressing nitrogen between V5 to V7 in corn allows you to apply nutrients before the crop gets too tall and ahead of pollination when nitrogen is in high demand. If you’re irrigating, I recommend adding nitrogen with each watering.      

Make use of tissue and soil testing results

Soil and tissue testing go hand in hand, providing valuable information for planning your fertility strategy. While your soil test indicates what nutrients are available for plant uptake, tissue testing reveals how effective nutrient uptake is. Even if your soil sample results show adequate nutrients, that doesn’t mean they will be available for your crop when it needs them. That’s why in-season tissue testing is critical.
In some cases, you may be able to make in-season amendments based on tissue sampling results. MAX-IN® foliar micronutrients are a convenient way to supplement plant nutrition in-season as you apply crop protection products.
In addition to nutrient deficiencies, also take note of nutrient ratios from your tissue sampling results. Pay attention to nitrogen to sulfur (N:S) and nitrogen to potassium (N:K) ratios. When these nutrient ratios aren’t balanced, plants can’t use nitrogen efficiently. As a general guideline, the N:S ratio for a high-yielding corn crop should be around 10:1. WinField United research shows that sidedressed potassium can be beneficial when N:K ratios are above 1.7:1. If ratios are below 1.3:1, more nitrogen may help improve yield potential. 

Focus on soil health

Many short-term actions help fine-tune your fertility plan, but building soil health over time is another practical way to improve nutrient use efficiency. As soil organic matter increases, nitrogen is cycled more efficiently, which can ultimately reduce application requirements. Building soil health also supports more yield stability and crop resiliency, especially during times of stress. Review your tillage methods, crop rotations and cover crop options to find opportunities to boost soil health.
For more fertility recommendations, talk to your local WinField United retailer.
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© 2022 WinField United. Important: Before use always read and follow label instructions. Crop performance is dependent on several factors many of which are beyond the control of WinField United, including without limitation, soil type, pest pressures, agronomic practices and weather conditions. Growers are encouraged to consider data from multiple locations, over multiple years and to be mindful of how such agronomic conditions could impact results. MAX-IN, and WinField are trademarks of WinField United. All other trademarks are the property of their respective owners.