The 2011 ASHS Annual Conference

A study was conducted to determine water requirements under Florida conditions for commercial production of sterile cultivars of Lantana (Lantana x hybrid 'New Gold' (NG) and Lantana camara 'Athens Rose' (AR)).  Sterile lantana cultivars are being considered as substitutes for commonly-grown cultivars that currently have high potential to hybridize with Florida’s native species.  Rooted cuttings for each cultivar were grown to commercial size under three different environmental conditions (open sun, shade house and greenhouse).  Daily water use was determined for separate sets of 10 plants by weighing each plant before and after a 24-hr period, 4 times a week. Plant canopy height and width were measured for each plant during the same period.  Evaporative demand was estimated using pan evaporation devices located in each growing environment.  Stepwise multiple regression (for R² improvement) techniques were used to develop best-fit water requirement prediction models using the measured parameters.   Models for each cultivar were validated using independent data sets collected at other times.  The resultant predictive models for NG and AR had R² values of 0.85 and 0.87 (p<0.01), respectively.  Pearson’s correlation determinations for measured ET versus predicted ET values for each model resulted in correlation coefficient values of 0.87 and 0.90 (p<0.01) for NG and AR, respectively.  Results indicate successful development a simple, but useful tool for estimation of Lantana water requirements for a range of environmental and plant canopy conditions.