Bernard Boissier Tropical Collection Greenhouses (Parc du Moulin à Tan)

The collection began in 1971 on the initiative of Bernard Boissier, who ran the parks department of Sens from 1968 to 1985. It was first housed at the municipal horticultural site, on the grounds of the former slaughterhouses on quai Albert-Schweitzer. According to the Journal du Palais, a Victoria cruziana flowered there that very first year, a rarity in France at the time.

Under his successor Jean-Luc Boulard, in post from 1985 to 2013 and the designer of the Parc du Moulin à Tan, the collections moved to the park. Backed by the mayor, Jean Cordillot, the project led to the opening of new greenhouses on 7 July 2000, in the presence of the Secretary of State for Tourism, Michelle Demessine; the old greenhouses on quai Schweitzer were demolished the same year. Some accounts, which date the greenhouses to around 1970 with a restoration in 2000, in fact run the two sites together.

The park received the Jardin remarquable label in 2011, renewed in 2016. In 2018 a flood destroyed many plants and closed the park for about two months. A quarter of a century after opening, the greenhouses underwent works from July to November 2025, costing 500,000 euros. The completed works were inaugurated on 19 December 2025, when the site took a new name: the Bernard Boissier tropical collection greenhouses.

The greenhouses cover 600 m² to the left of the park entrance. None of the sources consulted names their designer. The complex has three rooms with distinct atmospheres: a house for cacti and succulents, a winter garden recreating a tropical forest, which takes up the largest volume, and an epiphyte house. The winter garden contains a pool in which the giant aquatic plants are grown.

The 2025 works, carried out over five months for 500,000 euros, were meant to bring the building up to current standards and make it safe. The secondary structure was replaced, as were the facades and the roof, now covered in double polycarbonate glazing. The greenhouses and their collections are looked after by the town's parks department, headed by Aurélien Loiseau.

The greenhouses hold nearly 1,500 species and varieties. The winter garden evokes a tropical forest stocked with useful plants: avocado, sugar cane, orange, pineapple, cacao, coffee, banana, date palm, vanilla and pomegranate. Its pool is home to giant water lilies, among them Victoria cruziana, along with the prickly water lily Euryale ferox.

The cactus house shows cacti and succulents, while the epiphyte house gathers orchids, carnivorous plants, bromeliads and other plants that grow on trees. Built up over more than half a century, these collections draw about 30,000 visitors a year according to the Journal du Palais.

The greenhouses stand just to the left of the entrance to the Parc du Moulin à Tan, at 28 chemin de Babie, beside the Vanne and Lingue rivers. The park covers 10 hectares according to Wikipedia and 16 according to the regional tourist board; it combines an arboretum, a landscaped rose garden, animal enclosures, woodland and play areas, and ranks among the most visited sites in the Yonne.

An hour is enough for the three rooms, longer if the walk continues through the park, which also hosts temporary exhibitions and workshops. The greenhouses make a welcome tropical refuge in winter, while the warmer months invite a visit combined with the outdoor gardens.