2014 ASHS Annual Conference

Properly scheduling irrigation for nursery container crops can be difficult in substrates having low water-holding capacity. To produce high quality plants, nursery managers often apply excess irrigation resulting in higher leaching and nutrient movement.  Therefore, a simple, automated, sensor-driven irrigation system was designed at Louisiana State University (LSU) to better regulate irrigation application volumes while adjusting for precipitation events. A study was conducted comparing the LSU irrigation system to a timed nursery irrigation system.  The study was conducted for six months beginning May 2013 at a container nursery operation in Folsom, La fitted with overhead irrigation. Two cultivars of Gardenia jasminoides, ‘Frostproof’ and ‘August Beauty,’ were grown in 11.4L containers under the LSU or timed irrigation systems.  Six months after initiating the study, growth index and biomass in ‘Frostproof’ were similar between irrigation systems while ‘August Beauty’ exhibited increased growth index, biomass, and leaf number under the LSU irrigation system. Overall, the LSU irrigation system applied 44% less irrigation and resulted in 64% less leachate compared to the timed irrigation system for the 6 month growing cycle. The LSU irrigation system is capable of reducing nursery irrigation consumption and leaching while producing similar or higher quality plants compared to a timed irrigation system.