The grounds of the Heleneum are a miniature botanical gem where Mediterranean, tropical and subtropical plants grow thanks to a particularly mild microclimate and the presence of the lake. There is a charming grotto created from volcanic rock and surmounted by a small balcony that offers an outstanding panoramic view of the lake and the surrounding mountains. 

The grounds are planted with a beautiful south-facing Engish-style garden, which favours the growth of large exotic conifers.  The garden is laid out along the East-West axis and includes a part of the lakeside.  The flat area along the lakeside is traversed by a path flanked by Canary Island palms (Phoenix Canariensis), from which smaller paths lead to the villa’s terraces.

It is worthwhile noting that among the various species to be found in the gardens, there are citrus plants from the collection of Sir Peter Smithers: Plane Shrub (Colletia armata), Daphne (Dafne himalayana), Paper Bush (Edgeworthia chrysantia), Wisteria (Wistaria sinensis), Flowering Ginger ((Edychium gardenerianum), Kahili Ginger (Edychium gardenerianum), Chilean Wine Palm (Jubaea chilensis), Kumquat (Fortunella margarita),White Mulberry (Morus alba), and the Japanese Timber Bamboo (Phyllostachis).

The Museum offers guided tours of the garden and the villa by appointment only.