Although I can’t find the date on the About Times Haiku page, I can only assume April 1st is the kigo (seasonal reference) that has justified this page of “Serendipitous Poetry from The New York Times“.
In addition to the 5-7-5 syllable “rule”, the NYT explain:
A proper haiku should also contain a word that indicates the season, or “kigo,” as well as a juxtaposition of verbal imagery, known as “kireji.”
They then admit:
That’s a lot harder to teach [as] an algorithm, though, so we just count syllables like most amateur haiku aficionados do.
It’s rather late in the day, so I’ll simply offer a picture of the weeds in my garden – a “juxtaposition of vernal imagery”, which is as close to a kireji as I can manage right now.