Background: Plant breeders are utilising an increasingly diverse range of data types in order to identify lines that have desirable characteristics which are suitable to be taken forward in plant breeding programmes. There are a number of key morphological and physiological traits such as disease resistance and yield that are required to be maintained, and improved upon if a commercial variety is to be successful. Computational tools that provide the ability to pull this data together, and integrate with pedigree structure, will enable breeders to make better decisions on which plant lines are used in crossings to meet both critical demands for increased yield/production and adaptation to climate change. Results: We have used a large and unique set of experimental barley (H. vulgare) data to develop a prototype pedigree visualization system and performed a subjective user evaluation with domain experts to guide and direct the development of an interactive pedigree visualization tool which we have called Helium. Conclusions: We show that Helium allows users to easily integrate a number of data types along with large plant pedigrees to offer an integrated environment in which they can explore pedigree data. We have also verified that users were happy with the abstract representation of pedigrees that we have used in our visualization tool.