Make adjustments to offset season delays.
Agronomy Bulletin 22 ─ Delayed Corn Planting ─ Northern Corn Belt
When corn planting is delayed due to inclement weather and poor field conditions, you can still take advantage of the compressed growing season and achieve reasonable yield results by adjusting your hybrid selection and managing cropping activities with later planting dates.
Factors to Consider
- Weather and soil conditions
- Planting schedule
- Maturity options
- Plant first. Prioritize your cropping activities and realize that planting corn in a timely manner is most important. Nitrogen can be sidedressed until the eight-leaf stage. Postemergence herbicides can be substituted for preplant and/or preemergence herbicides and still provide effective weed control.
- Consider the current date. Cloudy, wet weather and poor field conditions may create the need to switch to shorter-season hybrids. In the northern Corn Belt, corn planting should be the priority after May 1. Generally accepted guidelines or “rules of thumb” for hybrid selection are:
• Change from the fullest adapted maturities to a midseason hybrid after May 15.
• Change from midseason adapted hybrid to short-season hybrid after May 25.
• Change from a short-season hybrid to corn alternative after June 5.
- Prioritize your planting schedule. Plant the fullest-season, latest-flowering hybrids first as they will take the longest to reach blacklayer and generally have the potential for the greatest yield response to early planting. The next priority is to plant early flowering, full-season hybrids. Next plant later-flowering, short-season hybrids. Last-planted hybrids should be those considered early flowering and short-season.
- Do not work wet soils. Soil structure determines the ability of soil to hold and conduct water, nutrients and air necessary for plant root activity. Compaction occurs when soil particles are pressed together, reducing pore space. Heavily compacted soils contain few large pores and have a reduced rate of water infiltration and drainage. It can be a major issue in cool, wet years and will reduce yields far more than a short planting delay.
- Plant for a uniform stand. Maintain recommended planting speed for your target plant spacing. Increased planting speeds can result in poor stands and greater planting problems. If conditions indicate a prolonged cool, wet period after planting, increase planting populations 5 percent to 10 percent to compensate for potential emergence problems and seedling diseases.
- Determine recommended maturities. See Table 1. For recommendations for your local area, contact a trusted agronomist or crop consultant.
Many factors should be considered when selecting a hybrid. Start by prioritizing your planting schedule and knowing the maturity recommendations specific to your area. For more information, contact your local Mycogen Seeds commercial agronomist or trusted agronomic adviser.