Location: Horticultural Crops ResearchTitle: Potassium fertigation in highbush blueberry increases availability of K and other nutrients in the root zone
Submitted to: Fluid Journal
Publication Type: Trade Journal
Publication Acceptance Date: 5/30/2017
Publication Date: 6/23/2017
Citation: Bryla, D.R., Orr, S.T. 2017. Potassium fertigation in highbush blueberry increases availability of K and other nutrients in the root zone. Fluid Journal. 25(3):5-9.
Technical Abstract: Fertigation with nitrogen (N) increases growth and production relative to granular N applications in blueberry, but little information is available on whether there is any benefit to fertigating with other nutrients. The plants were grown on raised beds and irrigated using two lines of drip tubing per row. Treatments were initiated in 2016 and included fertigation (once a week from April to August) with sulfate of potash (SOP) or potassium thiosulfate (KTS), a single application (April) of granular SOP, and no K fertilizer. Each K fertilizer was applied at a total rate of 75 lb K2O per acre. Throughout the growing season, fertigation with SOP or KTS resulted in lower pH and higher concentrations of K, Ca, Mg, and S in soil solution under the drip emitters than either no K or granular SOP, while granular SOP resulted in higher concentration of K than any other treatment at 6 inches from the drip emitters (edge of the wetting front). By the end of the fist season, the fertigation treatments contained nearly twice as much extractable K, but less Ca and Mg in the soil than the non-fertigated treatments. However, none to the treatments had any effect on yield or leaf K concentration to date, which could be due to the fact that changes in blueberry tissue K usually occur a year or two after K fertilizer is applied. More time is needed to determine the benefits of fertigation with K in blueberries.