Orto botanico di Palermo

The earliest beginnings of the gardens go back to 1779, when the Accademia dei Regi Studi created the chair of "Botany and medicinal properties". A modest plot of land was allocated to develop a small botanical garden dedicated to the cultivation of plants with medicinal benefits, for the twin objectives of general learning and improving public health.
Initially a site near Porta Carini utilized a site of the former fortified bastions facing the seaside from the walls of the city. These bastions were demolished in 1774–1778 under the praetorship of Antonino La Grua Talamanca, marchese de Regalmici, and later Prince of Carini, and reassigned for the botanical gardens. This initial garden allotment soon proved too small, and in 1786 it was decided to move to the present site, right next to the Piano di Sant'Erasmo, best remembered for the unfortunate events that occurred there during the Spanish Inquisition. The site had been orchards belonging to the former villa Giulia. Patronizing the development was the praetor Bernardo Filangieri, count of San Marco and the noblemen Giovanni Battista Paterno Asmondo and Ignazio Vanni.
In 1789 construction of the main part of the administrative buildings of the garden commenced in a neoclassical style. It is constructed with a central building, the Gymnasium, and two side buildings, the Tepidariumand the Caldarium, designed by the Frenchman Léon Dufourny, who had also designed a part of the oldest section of garden, right next to the Gymnasium. Its rectangular layout is divided into four quadrangles, within which the species are categorised according to Carl Linnaeus' system of classification. The new garden was opened in 1795; in the ensuing years it was improved, with the Aquarium (1798), a great pool hosting numerous species…

Gymnasium, Calidarium and Tepidarium
The central neo-classical building, known as the Gymnasium, is located near the main entrance gate. Originally it was the main office of the Schola Regia Botanice (school of botany), the Herbarium, the library and the director's office.
Two smaller buildings are located either side of the Gymnasium in perfect symmetry. To this day they are called the Calidarium and the Tepidarium because originally they housed plants from warm and temperate zones respectively (caldo meaning "hot" in Italian).

Linneian section
This is the oldest section of the gardens, laid out in a rectangular shape and divided into four quadrangles, the "quatrains" (or quartini). Each quatrain is further divided into flowerbeds, within which the plants were originally organised along the lines of the Linneian system of classification. The design of this section has gradually changed over time to display certain specimens at the expense of others that are now gone. At the centre of this section, is the particularly evocative “cross”, the small plaza that results from the intersection of the central axis (the Viale centrale) with the tree lined avenue of palms (the Viale delle palme).

The Aquarium and other water features

The Aquarium, a large round pool divided into 24 sections, is located at the end of the central avenue. The design consists of three concentric rings which are divided into 8 wedges, each being a home to a variety of acqautic flora.
The "lagoon" is located a few metres further down from the Acquariam and is another ample water feature in which the plants are arranged informally. Other smaller ponds are located in the quatrains of the Linneian section.

The greenhouses
Over time the gardens have benefitted from the development of a series…

(See also the full list of species of plants growing in the gardens further below).

The gardens are currently home to at least 12,000 different species.
Having been developed during the great age of exploration, between the second half of the 19th century and the first decades of the 20th century the gardens became an important point of reference for the bigger botanical gardens of Northern Europe. Because of Palermo's favourable climate, they transferred a good number of unknown, poorly classified and exotic tropical species there. In this context, the relationship between the Berlin Botanic Garden, under the stewardship of Adolf Engler, and those of the originating areas of the New World proved to be extremely important.
As an illustrative example of the role of the Palermo Botanic Garden, consider the introduction into the Mediterranean of the mandarin (Citrus deliciosa) and the loquat (Eriobotrya japonica).
The early Linneian plantings consisted of 1,580 different species, of which 658 still exist. Of these specimens, the most notable is the mighty Ginkgo biloba.

In the Aquarium many species of Nymphaea are to be found, including Nymphaea alba, Nymphaea tuberosa hybrids of Nymphaea × marliacea, the multicoloured Nuphar lutea and Nelumbum nucifera. Moreover, in the areas further in that are not submerged but humid nevertheless, one finds Alocasia, Colocasia, Zantedeschia, while in a nearby pond, the so-called laghetto, Egyptian papyrus (Cyperus papyrus) and other cyperaceae such as Scirpus lacustris and Cyperus alternifolius are absolutely thriving.
Various species of bamboo grow nearby and directly behind here, atop a small artificial hill, there is a healthy specimen of the drago tree (Dracaena draco). Not too far away one can see the tallest plant of…

For a few years now the gardens have been home to a colony of parrots of the species Psittacula krameri, having escaped from the aviaries of the nearby Villa Giulia and are perfectly at home in the subtropical habitat of the gardens.