Some spots in the county got 5 inches of rain last night after getting a few inches over Labor Day weekend. We got at least an inch in town last night. Once we make it to 7th week of bloom and beyond, we follow with an inch of irrigation per week. Since cotton is already set and its been hot and dry, we are having to continue irrigation. But when do we cut it off? It’s still a difficult decision to make – based on environmental conditions, how many bolls open, and how many bolls are mature. Below is information from 2014 UGA Cotton Production Guide from Extension Agronomist Dr. Guy Collins:
“It is generally recommended that irrigation be discontinued when a noticeable number of bolls have opened, especially when the majority of harvestable bolls are located on lower plant nodes. However, if the majority of the targeted harvestable bolls remain immature when just a few lower bolls begin to open, irrigation may still be needed for a short time.
Irrigation termination is a difficult decision. A final watering is often made when the crop begins to open. Commonly, no additional irrigation is applied once the time the crop is 10 percent open to minimize problems with boll rot, hard lock, and light spot. Common sense factors include prevailing weather patterns and predictions, available soil moisture, and time of year.”