CAN LOWBUSH BLUEBERRY SOIL PH BE TOO LOW?
A soil pH of 4.8 is often cited as being optimal for wild lowbush blueberry (Vaccinium angustifolium Ait.), but commercial fields range from 3.9 to 5.3. To determine if soil pH below the optimum is detrimental, two 1.2 x 2.4 m treatment plots within each of eight clones were established in a commercial field in Lamoine, Maine in 1994. One plot was randomly selected to receive 784 kg of sulfur per ha to create an extremely low soil pH of 4.0. Pretreatment 1994 yield data verified comparable fruit production of the two plots. Soil pH was significantly lower in sulfur-treated plots compared to control plots in 1995, 1997, 1998, and 1999. In 1998 the control pH was 4.6 and the sulfur-treated plots were 4.0. Despite this difference in soil pH, there were no differences between treatment plots in stem density (number of stems per unit area), stem length, branching, or flower buds/stem. In sulphur-treated plots, only minor increases in leaf N, P, and K concentrations and minor decreases in leaf Ca and B concentrations were found in 1997 samples. There were no differences in normal alternate-year yield of control or sulfur-treated plots in 1996, 1998, or 2000. Based on these results, soil pH as low as 4.0 does not appear to adversely affect growth or yield of lowbush blueberry.
Smagula, J.M. and Litten, W. (2003). CAN LOWBUSH BLUEBERRY SOIL PH BE TOO LOW?. Acta Hortic. 626, 309-314
Vaccinium angustifolium Ait., sulfur, nutrition