Some poems can serve as a memorial, but this one seems to be more of a poem which serves as (journey-based) artwork. I would suggest using instead
https://taginfo.openstreetmap.org/tags/artwork_type=poem
(note, wiki linked on this page is offline apr 26 and there have been some outages due to scrapers etc.)

Also, the name is either some word(s) of the poem (usually first line), maybe somewhere mentioned in the book they wrote about this route, or no name ( in which case noname=yes )

For your information; it is part of a route and you are welcome to look for the other plaques and create a route relation (or site type relation, if you prefer, though it is mostly not supported) which includes every plaque (without a role). This route can then have a 'url' for example
https://www.visitzuidlimburg.nl/te-doen-in-zuid-limburg/routes-in-zuid-limburg/detail/gedichtenroute/60121/
(since there seems to be no official 'website')