The cooler weather in the forecast for later this week has brought concern to those that still have peanuts in the ground and cotton not yet defoliated. Listed below are some thoughts to consider.
These temperatures this week will definitely slow peanut maturation down. However, temperatures in the lower 40’s and lower for several mornings in a row will cause the plants to shut down and further development and maturation will cease. That being said, be sure you allow a minimum of 48 hours (I prefer 72 hours) once peanuts are inverted before a frost or freeze. The risk for freeze damage is much higher at times shorter than this. Leave the peanuts in the ground if you are concerned about not having enough time before the cold arrives. Look at the upcoming days future forecast before you dig to be sure the temperatures will be warm enough.
Cotton growth and development is based on DD60s, with growth occurring mainly between temperatures of 60 to 94 degrees F. Once temperatures get below 60, cotton growth and development are minimal. This is important to keep in mind when considering when to defoliate. Not only does the temperature impact crop growth and development, but it also affects defoliation product efficacy.
Just like in peanuts we need to start thinking about first frost dates in cotton. It is best to be ahead of the frost to get as much benefit as possible out of the defoliants. Generally, you want to defoliate 2 to 3 days ahead of a frost to get those defoliants working before the plant shuts down.
Observe the local weather forecast and use it to help you make a decision, but MAKE a decision. If you think a damaging frost or freeze is likely in your area, try to get your cotton defoliated in a timely manner.