the gardens currently contain over 4000 specimens representing about 1000 species. the most important collection are desert plants, which include over 600 species from agavaceae, aizoaceae, cactaceae (about 400 species), didiereaceae, and euphorbiaceae. of particular interest are the gymnocalycium, mammillaria, and rhipsalis; alluaudia, aloe, and kalanchoe from south africa and madagascar; and notable specimens of "welwitschia mirabilis" from the south african desert. the garden also includes palms, ferns, conifers, carnivorous plants, and edible and medicinal plants, as well as a heated greenhouse for succulents (1000 m²).