This paper presents a concept of indicators for the environmental sustainability of farms, taking into account the capacity of the landscape to perform its essential functions within an extended accounting procedure. The objective is to represent the "resource capital of the landscape" of farms by means of indicators of landscape sustainability. Various existing indicator models for evaluating landscape performance functions of agriculture are compared, and the underlying evaluation indicators as tools of landscape planning and risk assessments are discussed. Certain landscape functions have been selected which appear to be suitable for describing the landscape resource of farms in cultural landscapes. The indicators used record the process development (erosion), the water balance (retention) as well as the landscape diversity (biotope, soil and crop type diversity) and the recreational function. The indicators were tested in five ecologically managed farms. As a result, a list of landscape indicators and evaluation methods are developed. The example of an evaluation of five farms for the wind erosion risk indicator shows that very varied action is required for wind erosion protection. Since the landscape resource as a significant aspect of sustained land management has been paid too little attention in the past, the stronger integration of functional landscape matters and landscape diversity into the economic and ecological evaluation of farm enterprises will be necessary in future. Function-based landscape indicators will be a powerful tool for the integration of agriculture into the landscape.