Early Season Frost Damage to Corn: Symptoms, Recovery, and Replanting

Weather Events Which Lead to Early Season Frost Damage on Corn

Different weather events can cause different levels of frost damage on corn. According to the National Weather Service, a frost advisory in the weather forecast indicates that the minimum temperature is forecast to be 33 to 36 °F on clear and calm nights during the growing season. A freeze warning is more concerning, as it indicates that widespread freezing temperatures are expected.¹ A temperature drop below 28 °F for one to two hours could be lethal to corn even with a belowground growing point.² ‘Simple’ frost appears on leaves with air temperatures warmer than 28 °F and the damage it causes is usually survivable. Even temperatures above 32 °F can produce ‘simple’ frost on leaves during clear, calm, early morning hours. Cool temperatures are an indication to scout. Injury symptoms and new growth should guide management after a frost event.

Symptoms of Plant Death and Frost Injury in Corn

Symptoms of frost injury begin to show on foliage about one to two days after a frost.² Corn leaves exhibit a water-soaked appearance, wilting, and a yellow and/or silver discoloration (Figure 1). Several days later, leaves may turn brown and die (Figure 2). Dead plants show no signs of recovery a week after frost and would have visibly damaged, dead tissue (including the growing point) below the crown. Dead growing points will be mushy and discolored and can be viewed by slicing corn plants down the center.

Why Corn Growth Stage and Growing Point are Important

The location of the growing point relative to the soil surface is a major factor in plant recovery from frost damage. When growing points are belowground, plants are expected to have a quick and nearly total recovery even after moderate frost events.³ The first four to five leaves can be killed off by frost with little long-term yield effect if the growing point remains belowground (Figure 3). The growing point of a corn seedling remains below ground until V6 growth stage and is protected from above-ground frost damage, unless the freeze was substantial.

Scouting Stand Count Versus Leaf Damage for Corn Plant Recovery

Universities recommend waiting three to five days after a frost to accurately assess potential plant damage.² However, new growth may be slow to unfurl if there are consecutive nights of cold temperatures, cloudiness, and rain as the prevailing conditions. Scout fields regularly. If new leaves are not emerging, check the growing point for discoloration. A white or cream-colored growing point that is still firm is an indication that the plant is recovering, while growing points that are darkened and soft are likely to die. A new leaf should develop three to four days after the frost if weather conditions are sunny with light to moderate winds (Figure 4).³

Frost Variability and Microclimates

Frost damage often varies across fields, ranging from light to severe. This variation in damage occurs because of slight differences in the topography of the field and other environmental conditions that create small variations in temperatures, or microclimates. Cool air is heavier than warm air, so colder air tends to sink to lower areas, which often causes low-lying areas of the field to receive the most damage from frost and cold weather events.⁴

Field microclimates can also be affected by cultural practices. A study conducted in Nebraska found that more frost damage was experienced by recently cultivated than uncultivated corn, and by non-irrigated corn compared to irrigated corn, respectively. Rows planted in a north-south direction were more frost damaged than east-west orientated rows. A crop rotation of corn following soybean was even found to have more resiliency to frost than corn following corn.³

Corn Replant Considerations

The existing crop stand should be evaluated for potential survival and uniformity before replant decisions are made. Since frost damage varies across fields, poor or missing stands may be a spotty occurrence. The yield potential of the existing stand should be compared with the yield potential of a replanted stand. In a Nebraska study of frosted corn at the V3 to V4 growth stage, defoliation up to 70% did not warrant replanting for yield benefits.^3,4 Seed availability, herbicide program, and soil conditions are additional factors that should be considered in successful replants.

Leaf Wrap and Clipping

Occasionally, decaying leaf tissue may inhibit the growth of new leaves from the whorl, giving the corn seedling a twisted appearance also known as “buggy whipping” (Figure 4). In most situations, the new leaves will grow through decayed tissue as it dries. Clipping or mowing for the purpose of clearing dead foliage has shown inconsistent yield results and increases the potential for spreading bacterial soft rot.^3,4

Sources

¹Watch/Warning/Advisory Definitions. National Weather Service, Weather Forecast Office. https://www.weather.gov/lwx/warningsdefined#Freeze%20Warning
²Nielsen, R.L. 2020. Assessing frost/cold temperature injury to young corn. Purdue University, Corny News Network. https://www.agry.purdue.edu/ext/corn/news/timeless/FrostedCorn.html
³Elmore, R.W. Frost – Impact on early corn growth (before V4). Iowa State University. https://crops.extension.iastate.edu/encyclopedia/frost-impact-early-corn-growth-v4
⁴McMechan, J. and Elmore, R. 2017. Risk of freeze damage in early-planted, emerged corn. University of Nebraska–Lincoln. https://cropwatch.unl.edu/2017/risk-freeze-damage-early-planted-emerged-corn/
Web sources verified 04/22/2026. 1222_123451