Mainau Island: One of Germany’s More Unusual Gardens

The Mainau dahlia collection, over 130 varieties, one of the largest in Germany, is the most defensible reason to visit in late summer rather than spring. Dahlias peak August through October, which makes Mainau an autumn garden destination rather than merely a spring one. The tulips in April are the more Instagram-famous period; the dahlias in September are the more genuinely interesting horticultural sight, and the crowds are significantly thinner.

Mainau is a 45-hectare island in Lake Constance, connected to the southern shore by a short pedestrian bridge or accessible by ferry from Konstanz. The island is owned and managed by the Bernadotte family, descendants of a Swedish count who inherited it in 1853. Count Lennart Bernadotte developed it as a horticultural showpiece through the 20th century. The current result is 45 hectares of themed gardens, a Baroque palace, a butterfly house, and a reasonably good selection of restaurants.

It’s a day visit, not an overnight destination. The ferry from Konstanz takes about 15 minutes. A pedestrian bridge connects to the lakeside at Mainau harbour if you’re driving to the area.

What Makes It Worth Visiting

The gardens peak at different times of year. Tulips and spring bulbs in April. Rhododendrons and roses in May and June. Dahlias (over 130 varieties, one of the largest collections in Germany) from August through October. There is almost no time of year when something interesting isn’t in flower.

The Baroque Palace, built by the Teutonic Order in the 1740s, is open to visitors. The interiors include the Hall of Knights with original painted ceilings, and collections of furniture and art from the Bernadotte family. The palace church (Schlosskirche) from the same period is small and ornate, with a notable painted altar.

The Butterfly House is the most reliable crowd-pleaser for families: a humid tropical greenhouse with free-flying exotic butterfly species. A bit relentlessly cheerful, but worth 30 minutes. Separate ticket from the garden entry.

The Mainau Island Lighthouse at the southern tip is a 15-metre tower with lake views. Not spectacular, but a pleasant walk to reach it through the less-crowded southern end of the island.

Admission and Timing

Adult entry runs around €22-25 depending on season. Combined tickets including the butterfly house are slightly more. Book online to avoid queues at peak times (Saturdays in May and June can be crowded). The island is open year-round, but winter hours are reduced and the gardens are obviously less dramatic.

Come early (opening is 9am in season) or late afternoon. The boat trip from Konstanz takes 15 minutes and the ferries run frequently; check the schedule to time your return.

Where to Eat on the Island

Restaurant Schloss Mainau inside the palace building is the main sit-down option, serving Swabian and Baden food (Maultaschen, Bodensee fish, roast pork) at around €15-30 per main course. The Bodensee Felchen (lake whitefish) is good and local. Several cafes and snack bars throughout the island handle lighter options. A picnic on the lake-facing terraces is also a completely reasonable approach; the benches and grass areas are designed for it.

Base Yourself in Konstanz

Mainau makes sense as a day from Konstanz rather than as a standalone destination requiring accommodation. Konstanz itself is worth a half-day: the medieval old town, the 15th-century Konzil building on the harbour, and the lakefront promenade. Several good hotels in Konstanz from €80-150 per night. From there you can also do day trips to Meersburg (20-minute ferry, good wine town) and the island of Reichenau (UNESCO-listed vegetable-growing island with Carolingian monastery churches).