production of container crops. Using CRF instead of WSF is recommended to the landscape service industry as a best management practice to provide nutrients for an extended period ( Andiru et al., 2013 ; Chen et al., 2011 ). CRF include urea, ammonium nitrate
feasible, economically viable, socially acceptable, and based on sound science” ( Bartnick et al., 2005 ). The application of CRF is one of the several BMPs in the “Florida Vegetable and Agronomic Crop BMP manual” ( Bartnick et al., 2005 ). Understanding
Using CRF instead of WSF for container-grown plant production is thought to limit nutrient loss ( Haver and Schuch, 1996 ; Medina et al., 2008 ). CRFs have been identified as a best management practice because they supply small amounts of localized
nutrient release time based on 75% nutrient release from CRFs. The European Union has developed both standard and accelerated laboratory procedures for measuring N release from CRFs; however, researchers in the United States are still developing a universal
sustainable production ( Urbano, 1989 ). The use of controlled-release fertilizers (CRF) for crop fertilization has been touted as a means to reduce NO 3 -N leaching from containerized nursery crops ( Colangelo and Brand, 2001 ), and CRF is now widely used in
-grown nursery crops in North America and worldwide, are commonly produced using CRFs owing to the benefits derived from this fertilization method, such as reduced labor costs and improved nutrient use efficiency ( Alam et al., 2009 ; Chen et al., 2001 , 2011
container. The CRF was layered 1 inch under the top of the substrate. We use a randomized block design with 12 plastic 18-gal rectangular tubs (large storage tubs) filled with rainwater from surface ponds at the research center to create a submerged growing
more slowly available sources, such as CRFs, provides an alternative management practice to reduce nutrient movement. Unlike WSFs, CRFs release nutrients in smaller quantities over longer periods of time ( Shuman, 2002 ). Past research indicates
structures ( Handreck and Black, 2002 ; Wulfsberg, 2000 ). Consequently, they both have a high potential for moving with water once dissolved. Nitrogen leaching from CRF formulations depends on the dissolution and transport of nutrients through a polymer
the physiological requirement ( Oertli, 1980 ). Recent studies have shown that controlled-release fertilizer (CRF) applied as part of a citrus fertilization program could reduce N leaching on Florida sandy soils ( Alva and Tucker, 1993 ; Dou and Alva