Site-specific Management of Soil pH and Nutrients in Blueberry

Site-specific management of soil pH and fertilizers is one of the most promising strategies in precision agriculture and is potentially applicable to many horticultural crops, including blueberry.  Unlike most fruit crops, blueberry is adapted to low soil pH conditions in the range of 4–5.5 and has much lower requirements for essential nutrients.  Blueberry also prefers the ammonium form of nitrogen over nitrate-N.  Recently, we examined the effects of pH and N source on plant development and nutrient uptake in blueberry and found that the roots were sensitive to not only N form but also timing and concentration of the fertilizers applied.  In this workshop, I will indentify the thresholds and parameters for optimizing blueberry root growth and function in the field and present options for manipulating soil pH and fertilizers for maximum nutrient uptake efficiency.  Specifically, I will discuss the use of conventional elemental sulfur applications in conjunction with nontraditional approaches for reducing soil pH such as acid injection, sulfur fertigation, and use of acidified composts. I will also present information on ideal forms of fertilizer to apply to blueberry under various soil pH conditions. With proper consideration of all the information available, pH and nutrient management can be fine-tuned to local conditions in order to maximum profitability and quality of production.