Commercial Greenhouse Producers Can Produce High-Quality Annual Bedding Plants in Biopolymer-Based Biocontainers and Are Willing to Use Them

Reducing the use of conventional plastics by employing biopolymer-based biocontainers in containerized greenhouse crop production of ornamental plants could improve the sustainability of commercial greenhouse crop production. Our objectives were to quantify the growth and quality of herbaceous annuals grown in different biopolymer-based biocontainers in commercial greenhouses and quantify producer interest and willingness to use biocontainers in their commercial production systems. Seedlings of ‘Serena White’ angelonia (Angelonia angustifolia Benth.) and ‘Maverick Red’ geranium (Pelargonium × hortorum L.H. Bailey) and nine different container types were taken to six commercial greenhouses in the upper Midwest. This study utilized eight different types of biocontainers and a control: 1) 80% polylactic acid (PLA) and 20% Biores™ (BR); 2) 90% PLA and 10% lignin; 3) 50% PLA, 30% soy protein polymer (soy), and 20% BR; 4) 60% PLA and 40% soy; 5) 80% polyhydroxyalkanoates (PHA) and 20% dried distiller’s grains (DDGS); 6) 55% PLA, 35% soy, and 10% BR; 7) recycled PLA; 8) biopolyurethane-coated paper fiber; and 9) petroleum plastic (control). Plants were grown alongside other bedding annuals in each of the commercial greenhouses, and producers employed their standard crop culture practices. Data were collected to characterize growth when the majority of plants were flowering, while questionnaires to quantify producer perceptions and willingness to use, interest in different container attributes, and satisfaction were administered at different times during the experiment. Container type interacted with greenhouse to affect angelonia Growth Index (GI) and shoot dry mass (SDM), as well as shoot, root, and container ratings. For example, GI of angelonia grown in PLA/BR (80/20) containers at greenhouse B were 22% smaller than plants at greenhouse A. Alternatively, GI were similar (18.4–20.6) across all container types within greenhouse A. Container type and greenhouse did not interact to affect geranium GI or shoot rating, but did for SDM, and root and container ratings. Geranium SDM was similar (4.54–5.68 g) across container types at greenhouse E, while SDM of geranium grown in PHA/DDGS across greenhouses varied from 2.85–8.97 g.  Root ratings for geranium grown at greenhouse G were similar except for container types that incorporated soy, compared to greenhouse C where plants in all container types except PLA/soy/BR (50/30/20) were similar. These results indicate that commercial producers can grow herbaceous annuals in wide range of biopolymer-based biocontainers with few or no changes to crop their culture practices.