In the UK, the term "silly season" refers to a period from roughly August to September during which Parliament and the Law Courts are not in session, and consequently, during which there is less hard, political news to report upon.
This concept exists in other countries too, with other Commonwealth nations, like Australia, New Zealand, and South Africa sometimes applying it to the Southern Hemisphere's summer months (roughly aligning with the Christmas and New Year holiday period), and in the US the "slow news season" refers to the same concept and time frame, adjusted for the US government’s schedule.
Most countries with a free press have some version of this same concept, ranging from the "Sommerloch" (summer news-hole) in German-speaking European nations, to "la morte-saison" (the dead/dull season) in France and the “nyhetstorka” (news drought) in Sweden.
Something approximating "cucumber season" or "cucumber time" is surprisingly common in reference to this same general idea across a wide variety of nations, including Iceland, the Netherlands, the Czech Republic, Hungary, Israel, and Slovenia, among other.
In most cases this term is a bit anachronistic, and while folks might generally know what you're talking about if you dropped it into conversation, they might not know you're specifically referring to a slow news period: historically the term has also been used to refer to a slow period in other industries, like tailoring—possibly because these sluggish intervals aligned with the high planting season for local cucumber varieties.
Whatever term we might use to refer to this period—which in most countries lines up with warmer months and with less political activity—a lack of day-to-day reportable hard news often results in more fluffy, unusual news items, including upbeat human-interest stories, but also pieces about sightings of the Loch Ness Monster and other headlines that would typically not make the cut on a more politically hopping day.
This concept is worth understanding because it helps explain why we see the news we see during different periods, and how our perception of what's important might thus be tweaked because journalistic entities tend to latently imbue the subjects of their reporting with a sense of vitality and importance.
It may be that our sense of what's vital and important changes from month to month, then, not because the actual properties of these things (be they political happenings or Loch Ness Monster sightings) have ebbed or flowed, but because the entities that report the news have relatively more or less consistent, hard news happenings to talk about.