Plants: Mighty trees, such as the now endangered elm, the native sweet chestnut, and even exotics like the Japanese bluebell tree, provide shade along the castle path (Burgweg). In the large meadows, various herbs, like thyme and comfrey, thrive alongside grasses. A lush flora also means a great deal of work. The grass, even on the steep slopes, is regularly mown. Whereas the castle hill was once kept as bare as possible for strategic reasons, nowadays the rocks must be repeatedly cleared of vegetation. The force of the roots, such as those of ivy, threatens to damage the masonry and the porous basalt tuff. 

Animals: Bees, ants, various beetles, and insects help maintain a biological balance. Hardworking squirrels collect their nuts, while lizards and snakes enjoy sunbathing on the rocks. The castle hill (Burgberg) provides a solid foundation for a diverse natural environment. Different species of bats, such as the long-eared bat and the horseshoe bat, leave the protective attic of the Riegersburg in the evening. Foxes and hares metaphorically say goodnight to one another here. The two moats also have their animal residents. While Hungarian “Zackel” sheep enjoy their life in the dry moat, goldfish and koi swim in the water-filled one.