The rose garden of the JBCLM has been designed with careful attention to the specific requirements of roses. Consideration has been given to soil depth, mulching with natural meadow vegetation, and optimal light conditions to ensure balanced growth. Inspired by the traditional Andalusi cruciform garden style, the layout includes paths forming a cross, defining four main planting beds. An adjacent greenhouse evokes the typical pavilions of such gardens, while the staircase of the 40th parallel serves as a viewpoint. At the centre of the crossing, where a fountain would traditionally be located, a sculptural trellis has been installed, created by local artist Santi Flores, supporting climbing roses and adding a contemporary touch to the classical design.

The arrangement of the beds highlights the historical and botanical richness of roses. Each space houses a specific collection: old roses (pre-1867), modern low-growing or shrub roses, landscape roses, and modern standard roses, surrounded by miniature roses in pots. This design allows visitors to appreciate the evolution of ornamental rose cultivation, from wild species to modern hybrids. The display also commemorates the milestone of 1867, when Jean-Baptiste André Guillot created the first modern rose, a cross between a tea-scented rose and a remontant rose, marking the beginning of thousands of new varieties.

The collection includes a diverse botanical selection well suited to the climatic conditions of the continental Mediterranean. Among the wild-origin or old cultivated roses are Rosa foetida and Rosa × centifolia, as well as varieties such as Reine des Violettes, Rosa Variegata di Bologna, and the ancient Rosa × damascena from 1254, attributed to the crusader Robert de Brie. Among modern roses, notable varieties include Red Devil, Perla Negra, Charles de Gaulle, and very recent cultivars such as Afrodita (2022). With its profusion of colours and fragrances, this rose garden combines aesthetics, history and science, making it a unique space for the enjoyment and study of rose horticulture.