The provided source material does not contain the actual article content about the Philadelphia museum project by Herzog & de Meuron and Piet Oudolf. Instead, the text consists entirely of cookie consent and data processing information from a website's privacy notice.

The article title suggests coverage of an architectural project involving the renowned Swiss architectural firm Herzog & de Meuron and Dutch garden designer Piet Oudolf in Philadelphia. However, without access to the actual article content, it is not possible to provide details about this museum project.

To properly report on this story, access to the original article content would be necessary to include information about the museum's design, timeline, location within Philadelphia, and the collaborative work between the architects and landscape designer.