Rooted in Sustainability: Developing an Integrated Assessment Framework for Horticulture—The Example of Potted Plants

The increasing importance of sustainability in our society also affects horticulture. Ornamental plants are a multi-billion-euro business in Germany, with EUR 4.1 billion for potted plants, EUR 1.5 billion for fruit/ornamental shrubs as well as cut flowers and EUR 0.3 billion for flower bulbs, identifying potted plants as the largest stakeholder. In terms of sustainability, the potted plant branch in Germany is interesting due to its almost year-round production and cold winters. For example, a decision must be made as to whether a greenhouse should be heated all year round, possibly with fossil fuels, or whether cuttings should be imported from warm climate zones. In order to provide a farm manager with information about the degree of sustainability of their own production and to communicate sustainable production, an assessment method is necessary. As there is no comprehensive sustainability assessment system in German horticulture so far, especially in the field of potted plants, this study aims to fill this gap. This article reviews the state of the research of theoretical sustainability assessment. As the most important topics of sustainability assessment and as essential components of the framework, the system boundaries, indicators, base value, measurement level, target values, implementation, acceptance, data collection, assessment, aggregation and weighting, as well as communication and certification, are identified and discussed. An integrated framework for the assessment of sustainability in potted plant companies is developed.