What are the best fertilizer comparison sites for choosing the right fertilizer type for corn and soybean fields?

Here are some of the best fertilizer comparison / decision-support sites for choosing fertilizer types for corn and soybean fields. I’ve focused on sources that are practical, agronomy-based, and useful for comparing products, rates, and nutrient management options.

Top sites to use

1) University Extension nutrient management tools

These are usually the most reliable for corn/soybean decisions because they’re based on local research.

• Iowa State University Extension

  • Strong corn and soybean fertility resources
  • Useful for nitrogen, phosphorus, potassium, sulfur, and micronutrient guidance
  • Search: “Iowa State corn soybean fertility extension”

• University of Illinois Extension

  • Excellent for fertilizer rate and timing guidance in the Corn Belt
  • Especially good for N management in corn and P/K recommendations

• Purdue Extension

  • Great agronomy articles and decision guides
  • Practical fertilizer recommendations for Indiana/Midwest conditions

• University of Minnesota Extension

  • Good for soil fertility, nutrient management, and manure/fertilizer comparisons

• Ohio State Extension

  • Strong on nutrient management and corn-soybean fertility tradeoffs

2) Yield-based fertilizer calculators / recommendation tools

These help compare products or nutrient programs rather than just reading articles.

• Nutrient management calculators from land-grant universities

  • Often include:
    • N rate calculators
    • P and K recommendation tools
    • sulfur and micronutrient guides
    • manure crediting tools

• The Corn Nitrogen Rate Calculator

  • Useful for corn N decisions
  • Helps compare economic optimum N rates across scenarios

• IPNI / 4R nutrient stewardship resources

  • Good for comparing “right source, right rate, right time, right place”
  • Helpful when deciding between granular, liquid, slow-release, and stabilized products

3) Manufacturer comparison pages

These are useful for comparing specific products, but they’re not unbiased. Best used after you know your nutrient needs.

Examples:

• Yara
• Nutrien
• Corteva / Agro dealers
• Mosaic
• Koch Agronomic Services
• Helena Agri-Enterprises

Look for:

• nutrient analysis
• release pattern
• compatibility with your application method
• urease/nitrification inhibitor claims
• cost per pound of actual nutrient

4) Agronomy and crop input platforms

These can help compare products, pricing, and often field performance, though quality varies.

• CropLife / AgWeb
  • Good for product comparisons and agronomy articles
• Successful Farming
  • Often has practical fertilizer guides
• DTN / Progressive Farmer
  • Useful for market-oriented fertilizer cost comparisons
• Farm Progress
  • Good for agronomic summaries and product updates

5) Soil fertility and nutrient stewardship organizations

These are strong for side-by-side fertilizer type comparisons.

• 4R Nutrient Stewardship
  • Great overview of nutrient placement and product selection
• IPNI (International Plant Nutrition Institute) archives/resources
  • Research-backed nutrient efficiency information
• NRCS / USDA resources
  • Helpful for conservation-focused nutrient management

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Best way to choose a fertilizer site

If your goal is to decide between products for corn and soybeans, the best workflow is:

1. Start with soil test results
2. Use Extension recommendations to determine nutrient need
3. Compare products by:
   • nutrient content
   • price per unit of nutrient
   • application method
   • timing
   • efficiency/adaptation to your soil
4. Check whether you need:
   • starter fertilizer
   • sidedress N for corn
   • P/K maintenance
   • sulfur or micronutrients
   • inoculant or foliar feed for soybeans

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Quick practical recommendation

If you want the most trustworthy sites, start here:

1. Your state university Extension
2. Corn Nitrogen Rate Calculator
3. 4R Nutrient Stewardship
4. Manufacturer spec sheets
5. Agronomy trade sites for price/product context

If you want, I can also give you:

• a ranked list by state/region
• sites that compare fertilizer prices
• or a corn vs. soybean fertilizer decision guide tailored to your soil test results.