SOIL TEXTURE AND LOWBUSH BLUEBERRY (VACCINIUM ANGUSTIFOLIUM AIT.) LEAF NUTRIENT CONCENTRATION INFLUENCES RESPONSE TO GYPSUM APPLICATION
Application of gypsum has been shown to enhance the release of soil nutrients and improve the nutrient status of plants in some but not all lowbush blueberry fields. A field survey was conducted to determine underlying factors that might contribute to this inconsistency regarding gypsums effectiveness. Preemergent applications of gypsum (4484 kg ha-1) or DAP (448 kg ha-1) were compared to untreated controls at eight commercial blueberry fields. Soil characteristics, soil and leaf nutrient concentrations, and berry yield were measured. Leaf N concentrations were improved by gypsum in only three of the eight fields. Leaf P concentrations were raised in six out of eight lowbush blueberry fields. Logistic regression analysis indicated that gypsum was effective only in fields initially deficient in leaf N, and fields having high soil clay content.
Santiago, J.P., Smagula , J.M. and Dail, D.B. (2014). SOIL TEXTURE AND LOWBUSH BLUEBERRY (VACCINIUM ANGUSTIFOLIUM AIT.) LEAF NUTRIENT CONCENTRATION INFLUENCES RESPONSE TO GYPSUM APPLICATION. Acta Hortic. 1017, 515-524