There are usually quite a few people on the Hauptstrand Büsum from November to February.
From November to April the water at Hauptstrand Büsum is too cold to swim in.
From July to January Hauptstrand Büsum has rainy season. This is something to keep in mind when planning your trip since it is quite possible that you may be unable to sunbathe.
Diving
Kiting
Surfing
Windsurfing