Soil-applied Sulfur Affects Elemental Leaf Content and Growth of `Tifblue' Rabbiteye Blueberry

Abstract

Two-year studies were conducted on 4- to 6-year-old rabbiteye blueberry (Vacciniun ashei Reade) plants grown on a high (6.6) pH soil and irrigated regularly with water containing moderate amounts of Na and Ca (32 and 15 ppm, respectively). In one study, various levels (0, 280, 560, and 1120 kg·ha-1) of elemental S were applied in a single annual application. In another study, a single level (1120 kg·ha-1) of S was applied annually in either one, two, or four applications. Applications of S at up to 1120 kg·ha-1 were not detrimental to plant vigor of rabbiteye blueberries. Soil pH decreased with successively higher levels of applied S. Leaf P, K, and Mn contents were higher and soil pH was lower with single compared with multiple applications of S. Soil K, Ca, Mg, and S levels were negatively correlated with plant growth. Amounts up to 1120 kg·ha-1 of applied elemental S were not sufficient to lower soil pH to a level desirable for rabbiteye blueberry production when the soil was irrigated 7 months·year-1 with water containing moderate amounts of Na.