Search Results (2)

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 (ET_A) 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 ET_A 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 ET_A 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 ET_A of crop 2 differed from 5.7 to 136.8 mL with a mean of 74.0 mL. Both crops had a cumulative ET_A of 9.4 L. Such differences in daily ET_A and cumulative ET_A 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 ET_A and cumulative ET_A values of the ferns with the other studied foliage plants indicated that daily ET_A and cumulative ET_A are species specific. Therefore, to improve irrigation efficiency, daily ET_A and cumulative ET_A values of major container-grown plants should be established. Implementing the research-based daily ET_A and cumulative ET_A in container plant production should reduce irrigation water leaching and runoff and conserving freshwater resources. Full article

Irrigating plants based on their water requirements enhances water use efficiency and conservation; however, current irrigation practices for container-grown greenhouse plants largely relies on growers’ experiences, resulting in leaching and/or runoff of a large amount of water. To address water requirements of greenhouse-grown plants, this study adapted a canopy closure model and investigated actual evapotranspiration (ET_A) of Calathea G. Mey. ‘Silhouette’ and Stromanthe sanguinea Sond. from transplanting to marketable sizes in a shaded greenhouse. The daily ET_A per Calathea plant ranged from 3.55 mL to 59.39 mL with a mean cumulative ET_A of 4.84 L during a 224 day growth period. The daily ET_A of S. sanguinea varied from 7.87 mL to 97.27 mL per plant with a mean cumulative ET_A of 6.81 L over a 231 day production period. The best fit models for predicting daily ET_A of Calathea and Stromanthe were developed, which had correlation coefficients (r²) of 0.82 and 0.73, respectively. The success in modelling ET_A of the two species suggested that the canopy closure model was suitable for quantifying water use of container-grown greenhouse plants. Applying the research-based ET_A information in production could reduce water use and improve irrigation efficiency during Calathea and Stromanthe production. Full article