13/07/2025
The frosts are here 🥶🥶🥶
Keep in mind that the effectiveness of herbicide control can be limited by these low temperatures.
Frost and near frost events cause the biological activity of plants to come to a halt and it won’t start up again until the plant warms to at least 5°C. Even then it will be very slow which is why we see reduced growth rates in colder temperatures.
On cold days, a few hours of between 5°C and a daytime peak of 10°C would not be enough warmth to get plant metabolism active to a point where herbicide was all that effective, especially with any cloud cover. In a nutshell, no biological activity = no herbicide activity.
For best results from winter herbicide control, you really need a day or two of warmer temperatures and sun with night time lows of 5°C or higher before spraying.
If the chemical is applied a minimum of 48 hours before a frost event, efficacy on living plants will be retained and the plant will continue to decline when it warms up again.
Pop in and see our team of agronomists at CRS to discuss how to get the most bang for your buck when controlling weeds this winter.
