Daily Water Requirement of Container Grown Davallia bullata and Nephrolepis exaltata and Implication in Irrigation Practices

Abstract

Container crop production has become increasingly popular, but daily water requirements of those crops from transplanting to marketable or harvestable stages are largely unavailable. To address this concern, daily water consumption of two container-grown fern species, Davallia bullata and Nephrolepis exaltata from initial transplanting to marketable size were studied using a canopy closure model. Daily actual evapotranspiration (ETA) of D. bullata ranged from 4.6 mL to 76.5 mL with an average of 29.0 mL per plant per day. The mean cumulative ETA was 13.2 L during 431 days of production spanning from 8 November 2006 to 4 February 2008. Two crops of N. exaltata were produced. Daily ETA per N. exaltata plant produced in crop 1 varied from 19.0 to 241.2 mL with an average of 69.5 mL, and daily ETA of crop 2 differed from 5.7 to 136.8 mL with a mean of 74.0 mL. Both crops had a cumulative ETA of 9.4 L. Such differences in daily ETA and cumulative ETA between the two fern species raised further concern of irrigation practices in commercial foliage plant production as multiple species are commonly produced in one greenhouse and share the same irrigation schedule. Comparing daily ETA and cumulative ETA values of the ferns with the other studied foliage plants indicated that daily ETA and cumulative ETA are species specific. Therefore, to improve irrigation efficiency, daily ETA and cumulative ETA values of major container-grown plants should be established. Implementing the research-based daily ETA and cumulative ETA in container plant production should reduce irrigation water leaching and runoff and conserving freshwater resources.