Frost versus freeze. The two terms are often used interchangeably, but the two weather conditions can have very distinct effects on corn plants. That’s because below-freezing temperatures make quite a difference in the severity of damage, depending on how cold the temperatures actually get.
Frost injury occurs when temperatures dip below freezing for a short period of time, harming corn leaves. Meanwhile, freezing injury occurs when temperatures are below 28 degrees for several hours, and can have a damaging impact on the entire plant.
To determine if your corn has been damaged by a freeze, examine the plant after several days to see if there is new growth. Warm sunny days are best, because they help determine if there will be new growth coming from additional plant emergence in the form of healthy green tissue. If the growing point was still below the soil surface at the time of the freeze, the chances the plant will survive are higher. If the growing point was damaged, it will have brown coloration and a mushy texture.
On the other hand, if you experience cool, cloudy weather following a freeze, that’s another obstacle in itself. The lack of sun and warmth could prevent the plant from growing as fast as it could, and the dead tissue would not deteriorate as easily. This can cause the plant to tie up the new leaf tissue as it emerges from the whorl.
Because colder air sinks further into lower lying areas in the field, make sure to monitor these sections of the field first. In the case of injured corn, flag the plant, then check back in another 3 to 4 days to see how the corn is responding.
In situations where plant loss occurs, consult stand charts to determine possible yield affects. This will help you determine whether a replant is needed. Contact your Golden Harvest Seed Advisor to help you make the best management decision or for additional agronomic insights.
Photos are either the property of Syngenta or used under agreement.
Syngenta hereby disclaims liability for third-party websites.