Despite not having been released as a single, "Wildflower" became a sleeper hit and has charted within the top ten in Greece, Iceland, Malaysia, the Middle East, Portugal, and the United Kingdom as well as within the top 20 in Australia, Canada, the Czech Republic, Ireland, Lithuania, Luxembourg, New Zealand, Singapore, Switzerland, and the United States.

The performance marked her return to the show after she first appeared on an episode in August 2017, seen as a milestone that helped shape her subsequent breakthrough.

[3] On October 19, Eilish performed the song as part of her Saturday Night Live set, accompanied by her brother Finneas O'Connell on an acoustic guitar.

[5] In a deeper analysis, Alex Hopper of American Songwriter opined that "Wildflower" serves as a "pseudo apology" to Carlson, in which Eilish depicts the end of their relationship.

According to writer Hannah Dailey, the "soulful and gloomy" song encompasses her "most mature songwriting yet", crafted to make "a complex story look simple" as she obsesses over her partner's ex-girlfriend.