Passwords suffer from major usability hurdles that foster insecure practices and undermine cybersecurity. Passkeys were introduced to address these issues, however, adoption remains low. Digital nudges offer a promising way to accelerate passkey adoption, yet research lacks empirical insight about when to nudge and which nudge types and designs are most effective. We therefore employed a mixed-methods approach to examine the impact of nudges on passkey adoption across five touchpoints in the digital user journey: During registration, login, account recovery, while in the settings menu, and during user activity. First, we conducted 15 expert interviews to identify candidate nudges and their design principles. We evaluate these nudges in a randomized controlled trial (RCT) with 3,680 participants on a commercial healthcare platform. Our results indicate that digital nudges can significantly increase passkey adoption when applied at the right touchpoints, encouraging users to move beyond passwords.