Seishun no Hana / Start Line (青春の花/スタートライン; Flower of Youth / Start Line) is Kobushi Factory's 8th and final single. It was released on March 4, 2020 in four editions: two regular and two limited.[1] The first press of the regular editions include a random trading card of 6 kinds depending on the jacket (12 in total).
"Seishun no Hana" was digitally pre-released on February 12, 2020 through iTunes,[2] and "Start Line" was digitally pre-released a week after it, on February 19.
For a limited time, fans who purchased the single at select stores would get one of six clear ticket holders as a bonus.[10]
Towards the end of "Seishun no Hana", the members sing the same "la la la" part that was featured at the beginning of "Shalala! Yareru Hazu sa" while mimicking the choreography.
Starting February 29, all release events for the single were cancelled in consideration of a new policy established by the government to prevent the spread of COVID-19.[11]
As a result, this is their lowest selling single, lowest ranking single, and also their lowest first week sales.
This is their only major single to not have an Event V.
The embedded subtitles of the "Seishun no Hana" music video on YouTube has a typo at the 2:02 mark. Instead of "spit", it says "split".