The girl claims to have no memory of why she was tied up or how she came to be in the vineyard.
According to the police report, a cyclist found the child lying between two rows of vines at around 7:30 pm and called for help after the girl did not respond to his questions.
Shortly after, walkers who were nearby came to their aid and the girl then began to respond.
The 11-year-old told local authorities that the last thing she could remember was visiting a supermarket before walking towards a nearby bridge through an underpass.
Police are investigating the strange circumstances, but the child is yet to offer up any more information, saying she cannot remember what happened.
A forensic investigation of the plastic used to tie the girl's hands is underway and could provide the necessary clues to solve the mystery.
A representative of the Heilbronn police told the Stuttgarter Nachrichten that there is a possibility the girl carried out this stunt for attention and that the case "should be cleared up fairly quickly", after further investigation.