Maximum allowed time for PhD (Doktor) in Germany
The typical times for a PhD in Germany vary mostly between three and six years, depending on the specific field you're in.

Legally, the university is allowed to give you fixed-term contracts for a total maximum of six years while you're working towards your PhD. However, there are extensions of this limit for childcare, so you would be well below this limit.

For a postdoc position, I don't think the time taken for your PhD would be a major factor in evaluating your application.