Adopting technology to achieve environmental stewardship is a high priority among greenhouse industry members. Zero runoff crop production systems can protect surface and ground water and use water, fertilizer, and labor resources more efficiently. However, scarce capital and fear of new technology are impediments to change. Our objectives were to characterize decision making and profitability related to zero runoff systems. Managers of 80 greenhouse operations with zero runoff systems in 26 states participated in a survey designed to gather information on the costs–benefits of adoption and production changes and issues related to zero runoff systems for greenhouse operations. The survey results revealed that some adjustments of production practices were essential when adopting zero runoff systems. It also appeared that greenhouse operators believe they are achieving the intended outcomes and efficiencies from their investment. Size of the operation appeared to be closely linked to the growers' willingness to adopt this new technology. Important reasons for making the decision of adopting zero runoff systems were to improve quality of productions, cut production costs, increase production efficiency, and respond to public concern for the environment. Two thirds of the operators surveyed found that special employee training in the operation of zero runoff systems was required. Most employers found in-house training was adequate for their needs. Operators verified that a significant learning curve slows implementation of zero runoff production Adjustments of cultural practices coupled with good production management were keys to growing zero runoff successfully.

Zero runoff subirrigation (ZRS) technology is a promising method of managing fertilizer and pesticide inputs while improving production efficiency. However, high capital investment costs and inadequate technical information available to growers are major impediments to initiating the change. This study quantifies costs and returns associated with adopting ZRS systems and compares the profitability of four alternative ZRS systems (ebb-and-flow benches, Dutch movable trays, flood floors, and trough benches) for greenhouse operations in the northeastern and north central United States. The capital investment analysis showed that the Dutch movable tray system was most profitable for small potted plant production, and the flood floor system was most profitable for large potted plant and bedding crop flat production. Sensitivity analysis showed that changes in cost variables generally did not affect the profitability rankings of the alternative ZRS investment projects. Nonetheless, the flood floor system gained slight advantages when the product price increased, and the Dutch movable tray system gained advantages as the hourly labor cost increased.

A renewed interest in perennial garden plants occurred during the 1980s. The need for more information on how to force the plants for flower-show exhibition prompted this research. Experiments were designed that combined the effects of cold storage, daylength, and greenhouse temperature on the development of perennials. The six species and cultivars studied were categorized by the interaction of cold and daylength on their growth and flowering strategy.

Zero runoff subirrigation (ZRS) technology can effectively manage fertilizer input while improving greenhouse production efficiency. However, high capital investment costs and inadequate technical information to growers are impediments for adoption. A Monte Carlo simulation was used to compare the profitability and risks of alternative ZRS system investments for greenhouse operations in the northeastern and north central United States. Results showed that the Dutch movable tray system and the flood floor system were most profitable and least risky for small potted plant and bedding crop flat production, respectively. The trough bench system was least favorable because its profitability was low and highly volatile.

Cold temperature treatments stimulated inflorescence formation of Aguilegia × hybrida at the 12-leaf stage. Long photoperiods slightly advanced flowering further, but caused petiole elongation. Sprays of butanedioic acid mono-2,2-dimethylhydrazide (daminozide) at 2,000 mg/liter effectively prevented petiole elongation.