On the hillock overlooking the small pond, a rock garden has been recently created. It includes both acid and basic rocks, and gypsum rocks too, which can easily be found on the outcrops around Bologna.
The rock garden houses Italian species typical of these environments, characterized by morphological adaptations (leafy crassulence, pulvinate structure, hairy leaves, etc…) designed to resist extreme weather conditions of the rupicolous environment, both in the summer (strong daytime heat, drought, wind) and in the winter (frost and snow cover). These species are all slow-growing and therefore rare and protected.
Among these we mention edelweiss, carnations Dianthus plumarius and D. sternbergii subsp. marsicus (the latter an Abruzzese endemic specie), Cerastium tomentosum, shiny absinthe (Arthemisia nitida Bertol., an Italian endemic specie). Among the succulent: the houseleeks (Sempervivum tectorum L., S. archnoideum L. e S. montanum L.) and stonecrops (Sedum rupestre L., S. album L., S. dasyphyllum L. e S. maximum (L.) Suter).
The section with gypsum rocks contains species of the Gessi Bolognesi such as Thymus longicaulis Presl., Erysimum pseudorhaeticum Pol. and Teucrium flavum L.
