Evaluation of the Nutrient Status of American Cranberry in Latvia during 2001-2007

Being a native wetland plant, cranberry culture requires not much nutrients. However balanced and precise mineral nutrition is essential for producing high yield and quality. Surveys were carried out to determine the actual status and trends in mineral nutrition of American cranberries in Latvia during 2001-2007. Together 160 (peat and plant) samples were collected from different cranberry producing sites in Latvia over two periods: 2001-2004 and 2005-2007. Plant tissue analysis and soil testing were used to evaluate cranberry nutrient status (N, P, K, Ca, Mg, S, Fe, Mn, Zn, Cu, Mo and B). The results revealed several problems in the system of plant mineral nutrition. Insufficient levels of N, P, S, Fe, Cu, Mo and high concentrations of Mn were found. In general, our results suggest that only about 50% of plant tissue nutrient indices and 25% of soil tests were in the sufficient range. Positive trends in nutrient status of cranberries were found from 2001-2004 to 2005-2007. Indices in optimal range increased for N, P, S, B, Mo and element concentration range became narrower and closer to tissue standards. The lack of increased nutrient concentrations in peat samples indicated that cranberry fertilization practices in Latvia are likely not detrimental to the environment.