Gypsum Timing – Sullivan and Perry

— Written By

Hopefully fields have dried well enough to get fungicides, insecticides and herbicides out as well as gypsum. Mitch asked when the drop dead date for gypsum application will occur. I gave him the date of August 10 but I really don’t have data to support that. I happened to speak to Dr. Gene Sullivan this past week and talked about the crop and a number of other things. Some of you worked with Dr. Sullivan when he was the peanut specialist at NC State up until 1994. He stated that Astor Perry, the peanut specialist that preceded him, stated one time that “he believed he would put out gypsum on peanuts even after they were harvested.” I told Dr. Sullivan that I would use him as a ghost writer for Dr. Perry. If you look at the images from Peanut Notes No. 52 you will see that peanuts planted in mid and late May have very few pegs and pods present right now, and more will come on the May 3-planted peanut. Pegs, kernels and pods will need calcium all the way through their development. So while applying gypsum to harvested peanuts is late (Drs. Sullivan and Perry are being a bit humorous with that recommendation,) applying gypsum well into August will still help pods “be all they can be.”

Article first appeared as North Carolina Peanut Note (PNNC-2013-053)