Cotton Planting Conditions April 25, 2019
Keith Edmisten, Professor of Crop Science & Soil Sciences and Extension Cotton Specialist
Guy Collins, Extension Associate Professor – Cotton
Soil temperature at a 3-inch depth was 64.4 degrees at 8 this morning (April 24). Soil temperature quickly increased to almost 76 degrees by 4:00 p.m. The DD60’s predicted for the 5 days following planting at Rocky Mount are included in the table below. Conditions look pretty good at this point but can certainly change quickly as these predictions are based on a 10-day weather forecast. Note that planting on April 26 triggered a warning based on low temperature. Based on soil temperatures the past few days, growers should be able to plant that day, but they may want to check soil temperatures in the morning. Planting a larger seeded variety with high cool germ would certainly help. What is more alarming concerning planting today (April 25) or the following day, is that there is a 100% prediction of thunderstorms on the 26. This is especially concerning for those planting on soil that tend to crust. The 10-day prediction is for very little rain from April 27 through May 3.
The table below is for Rocky Mount and based on the 10-day forecast. As spring weather forecasts can often differ across the state, we strongly encourage you to get a more local forecast that can be easily updated daily using the new NC State University Cotton Planting Conditions Calculator. The calculator can be found on the Cotton website under the link “Calculators and Decision Aids” on the left-side toolbar, or directly on the Cotton Planting Conditions Calculator website. We encourage growers to use and monitor the calculator twice daily to account for potential changes in weather forecasts for your region or farm. Simply click on your farm location on the map, and click “submit” for your local planting conditions forecast.
It is certainly possible to achieve a good stand-in marginal conditions. Please consult Strategies for Planting Cotton in Suboptimal Conditions if you decide to plant under marginal conditions.
The chart below illustrates how we define planting conditions. We cap DD60’s at a maximum value of 10 for each day. If you are computing DD60 accumulation on your own and a day is predicted to have 15 DD60’s, only use 10 for that day. We also lower the planting conditions by one category if a low of 50 or less or DD60=0 is predicted on the day of planting.
|Relationship Between Predicted DD-60s and Planting Conditions.|
|Predicted DD-60 accumulation for five days following planting||
|10 or fewer||Very poor|
|11 to 15||Marginal|
|16 to 25||Adequate|
|26 to 35||Good|
|46 or greater||Excellent|
|Avoid planting cotton if the low temperature is predicted to be below 50°F for either of the two nights following planting or predicted daily DD60’s is near zero for the day of planting.|