Gypsum Applications and Excessive Water Peanut Notes No. 90 2020
The rates of gypsum recommended in 2020 Peanut Information hold for both dryland and irrigated production systems. There is concern that excessive rain and possibly over-irrigation can result in movement of calcium from the pegging zone further down in the soil profile. My biggest concern is not the water moving straight down from the soil surface but washing of soil off of rows into the furrow. One way to minimize soil washing is to make sure a considerable amount of growth has occurred prior to applying gypsum. Peanuts respond positively to gypsum even when applied through the month of July, although late-June applications are generally the norm. The peanut crop started slowly and continues to struggle because of cooler temperatures this week and cloudy weather that is coming along with the rain. If you are applying gypsum later than you normally do, in part because of rain this week, you are not behind.