Effects of Planting Depth on Corn Stand Establishment and Yield

Trial Overview

  • Accurate planting depth is directly related to even seed emergence, and is a critical aspect of creating the perfect environment for every seed.
  • Across the Midwest, 1.75 to 2.25 inches is the typical recommendation for corn seeding depth. This ensures good seed-to-soil contact, places seeds into adequate moisture during the planting window, and ensures the establishment of a strong nodal root system.
 

Research Objective

  • To evaluate the impact of planting depth on corn establishment and grain yield.
Location
Soil Type
Previous Crop
Tillage Type
Planting Date
Harvest Date
Potential Yield
Planting Rate
Huxley, IA
Clay Loam
Soybean
Conventional
05/31/2017
10/19/2017
220
34,000

Site Notes:

A 108 RM SmartStax® RIB Complete® corn blend product was used for the trial.Plots were planted with a 6-row John Deere® MaxEmerge® Plus planter fitted with Precision Planting® 20/20 SeedSense® and hydraulic DeltaForce® equipment.165 lbs/acre of anhydrous ammonia was applied in the spring before planting.Treatments consisted of 3 different planting depths: 1 inch, 2 inches, and 3 inches, with 5 replications.Each treatment was 6-rows wide and 200-ft long in 30-inch row spacing.

 

 

Understanding the Results

Figure 1. Corn seedlings depicting different mesocotyl lengths due to different planting depths. From left to right: 1 inch seeding, 2 inch seeding, 3 inch seeding.
  • Yields were positively correlated with final harvest population, where the 2 inch seeding produced the most plants at harvest and the highest yields, and 3 inch seeding produced the lowest harvest population and the lowest yield.
 

What Does This Mean for Your Farm

  • Uniform germination and emergence are required to optimize yield potential.
  • Achieving this depends on planting depth and the soil conditions (particularly moisture and temperature) during and after planting.
  • In dry, light textured soils, planting deeper than 2 inches may be required to place seeds where moisture levels are consistent to ensure uniform imbibition and germination.
  • In heavy textured soils, as at the site of this trial, seeding depth should not exceed 2 inches. While performance of the 1 inch seeding was comparable to the 2 inch seeding this season, this may not be the case in most years.
  • In most cases, planting shallower than 1 inch is not recommended.