Profitability of Sensor-based Irrigation in Greenhouse and Nursery Crops

Abstract

<jats:p>Improvements in sensor technology coupled with advances in knowledge about plant physiology have made it feasible to use real-time substrate volumetric water content sensors to accurately determine irrigation timing and application rates in soilless substrates in greenhouse and container production environments. Sensor-based irrigation uses up-front investments in equipment and system calibration in return for subsequent reductions in irrigation water use and associated costs of energy and labor, spending on fertilizer, and disease losses. It can also accelerate production time. We present formulas for assessing profitability when benefits and costs are separated in time and apply those formulas using data from an experiment on production of gardenia [<jats:italic>Gardenia augusta</jats:italic> ‘MADGA 1’ (Heaven Scent™)]. Sensor<jats:bold>-</jats:bold>controlled irrigation cuts production time and crop losses by more than half. Annualized profit under the wireless sensor system was over 1.5 more than under the nursery’s standard practice, with the bulk of the increase in profit due to the reduction in production time. These results indicate that controlling irrigation using wireless sensor systems is likely to increase profitability substantially, even if efficiency gains are not as high as those achieved under experimental conditions.</jats:p>

Substrate Volumetric Water Content Controls Growth and Development of Containerized Culinary Herbs

“…However, aside from implementing precision irrigation strategies for producing containerized crops, there are other benefits when using these systems in commercial applications. Automated sensor-based irrigation is not only used to restrict irrigation for controlling height [6] but also to improve water use [24], plant growth uniformity [27], biomass [28], flower number [29], plant stress symptoms, and disease pressure [30] and can increase profitability of commercial producers compared to visual inspection-or timer-based irrigation scheduling [31].…”

Grower demand for sensor-controlled irrigation

“…Research studies conducted in actual production environments indicate that these systems can reduce irrigation costs—including labor and energy in addition to water—substantially [ Belayneh et al ., ]. Other documented benefits include lower plant loss rates, shorter production times, less need for pesticide application, and higher yield and quality [ Lichtenberg et al ., ]. These research studies all indicate that adoption can be extremely profitable.…”

“…[] for a more detailed description). The potential value of more accurate information about the production environment has been demonstrated for variable rate fertilizer application [ Pautsch et al ., ; Bullock et al ., ] as well as for sensor networks [ Belayneh et al ., ; Lichtenberg et al ., ].…”

“…Previous studies also indicate that older growers are less likely to adopt new technologies, suggesting that willingness to adopt a sensor network should decrease as the age of the operator increases, a finding that has been attributed to a shorter time horizon and higher transition costs [ Feder et al ., ]. Research to date suggests that the payback period for investments in sensor networks is quite short [ Belayneh et al ., ; Lichtenberg et al ., ] suggesting that a shorter time horizon should not be an impediment to adoption. Once technological sophistication is taken into account (by controlling for education level, for instance), transition costs may not correlate with age.…”

“…For greenhouse and nursery uses, sensors that measure moisture in smaller volumes of substrate (currently about 350 mL) would increase usability. These technical improvements, combined with information about performance and reliability from experiments and commercial experience [e.g., Belayneh et al ., ; Lichtenberg et al ., ] should help increase expectations about profitability and reduce uncertainty about performance.…”