Starter Fertilizer in Corn: Updated

Eric Solberg, Eastern Product Agronomist
March 4, 2022

A year ago I wrote a blog on starter fertilizer in corn.  Things have changed a lot in the past 12 months, and starter fertilizer is more important than ever for raising a healthy corn crop.  I have updated the information below to put things in perspective.

$7.00 corn is something farmers love to say.  A year ago, corn was well over $4.00 a bushel.  March 2022 corn is $7.25 The corn market hasn’t been this high since the fall of 2012, that’s ten years!  With the outlook of strong grain prices, let’s look at one way to potentially increase your yields and profits for 2022.

Corn Prices – 10 year history



     Starter fertilizer is a concentration of fertilizer placed near the corn root zone at planting. A starter fertilizer increases the nutrient source for the newly formed root system and helps with any adverse conditions that may arise soon after planting. Starter fertilizer shows a greater response in no till and conservation tillage systems due to cooler soil temperatures and higher residue at the soil surface, conventional tillage systems don't show as consistent of a yield response.  

     Most starter fertilizers contain N(Nitrogen)-P(Phosphorus)-K(Potassium) at differing rates. 10-34-0 would be a good example of a common analysis of a popular starter fertilizer.  Starter fertilizers with a low salt content are ideal because there is less chance of hurting the germinating seedling.


  1. Orthophosphate fertilizers. Orthophosphate fertilizers are much more plant available and usually more expensive.
  2. Polyphosphate fertilizers. Polyphosphate fertilizers need warmer soil temperatures to convert to plant available phosphorus.

A combination of ortho and poly-based starter fertilizers are the most popular and the most economical. Usually, a 60/40 to 50/50 blend of the two are ideal.

The sweet spot for starter placement is ¾” over and ½” down from the seed, this is done by the 2x2 method. If placing starter directly in the furrow, which is very popular, make sure the fertilizer being used is high quality and low salt.  Starter fertilizer is not temperature sensitive so it can in theory offer a little “cold weather insurance.”  In very dry planting conditions if you are worried about having enough starter to germinate the seed, turn off the starter.


  1. Earlier than normal planting dates
  2. No-till with high residue cover or earlier than normal planting date
  3. Late planting dates
  4. Continuous corn, especially in no-till
  5. With lower than recommended P and K broadcast application rates

Starter fertilizer can help get your corn off to a healthy, uniform start to maximize yields. There are different starter fertilizer application methods to choose from, depending on your soil situation. To maximize results, use a starter fertilizer program that fits your farming practices and equipment. Every spring is different and has its own challenges, with the use of starter fertilizer when conditions aren't ideal it can give you a 7 to 10 bushel increase in yield plus a little peace of mind.  



  • Starter Fertilization Sometimes Boosts Corn Yield.  Antonio P Mallarino ISU Integrated Crop Management March 20, 2015
  •  Corn Prices – 59 year history