Biocontainer use in a Petunia ×hybrida greenhouse production system: A cradle-to-gate carbon footprint assessment of secondary impacts

This study assessed the material and energy inputs required to produce a Petunia ×hybrida plant from initial propagation to delivery at a regional distribution center. Impacts were expressed in terms of their contribution to the carbon footprint or global warming potential (GWP) of a single finished plant in a ≈10-cm diameter container. Beyond this baseline assessment, the study investigated the secondary impacts (e.g., irrigation demand) associated with container type used. Life cycle assessment data were sourced from interviews, published literature, propriety data sources, direct metering at the greenhouse facility, and original findings from a series of university greenhouse experiments. Results show that a traditional plastic container accounts for ≈16% of overall CO2e emissions (0.544 kg) during petunia production. Although the container was a significant contributor to GWP, electrical consumption for supplemental lighting and irrigation during plug production proved to be the leading source of CO2e emissions (over 47%) in our model system. Differences in GWP when considering secondary impacts associated with the various biocontainers were minor, especially when compared with the other elements of production. Our results demonstrate that biocontainers could potentially be as or more sustainable than plastic pots once pot manufacturing and end-of-life data are considered. However, use of more efficient supplemental lighting sources may ultimately have the greatest impact on overall GWP for the production system assessed.