Sustainable Conservation and Restoration of Historical Gardens

A garden is a complexity of components with very different evolution and decay rates (cit.) (Dezzi Bardeschi M, Restauro: punto e da capo. Frammenti per una (impossibile) teoria, a cura di V. Locatelli, 8a Edizione. Franco Angeli, Milano, 2009). In historical gardens, artworks are constituted by heterogeneous materials such as natural and artificial stones that are subject to different deterioration. The main decay phenomena depend on the characteristics of the original material, the presence of metal structures of completion, and environmental factors, both natural and anthropogenic. The environment and minerals salts favor the proliferation of flora and micro flora that are intimately related to the chemical composition and morphological structure, and the microbial communities with more biodiversity are those able to degrade the materials selectively. Other damages are due to accidents or vandalism. An interdisciplinary diagnostic approach is fundamental to understand the state of conservation of artworks outdoors, determine the causes of decay, and choose between restoration and maintenance intervention. Nonetheless, a sustainable choice of minimized intervention at a low impact on artworks and the environment is a priority. In this contribution, the research activity and the results obtained in several case studies are discussed.