Tucked away at the southern end of Karlsaue is a gem of landscape gardening: Siebenbergen, the »island of flowers«.
The artificial island, created in 1710 and redesigned around 1820, owes its Eden-like charm to Wilhelm Hentze, the man who became Court Garden Director in 1834 and remained in charge of the gardens of Electoral Hesse for decades. Hentze created a kind of botanical garden which integrated exotic plants into the native flora. He loved early-flowering plants in particular, and delighted in coaxing the island out of hibernation, turning it into a sea of corydalis, snowdrops, crocuses, and spring snowflakes. Today Siebenbergen is home to about a hundred species of plant from all over the world.
With the seasonally changing colours of its foliage, the sequence of flower plantings over the year, and the views across the surrounding water, the island provides spectacle throughout the spring, summer, and autumn months.