Exploring design space is an important process in finding solutions to a design task. In this paper, we present BloomGraph, an online application developed for florist apprentices to explore the space of bouquet designs. BloomGraph provides a graph-based interface that allows users to explore design variations as they follow the nodes in a graph. This paper presents the preliminary result from an experimental study with florist apprentices in vocational education in Switzerland. Based on the early findings, we discuss the potential of the application as a learning tool and address the next steps to be followed.