Depends on the frogs
(Shunmin akatsuki wo oboezu; “Spring sleep knows no dawn”)
The air of a night in spring feels good, and the nights themselves are getting shorter, so one ends up sleeping in instead of waking with the dawn as usual. Sleeping past the normal time to get up in the spring.
We begin with the compound noun – not one in common usage – 春眠 (shunmin), “spring sleep.” This is followed by, but separate from, the noun 暁 (akatsuki), “dawn,” marked by the particle を (wo) as the object of the verb 覚ゆ (oboyu), “to remember,” “to feel,” in imperfective form, with negative suffix ず (zu) in sentence-final form.
This phrase comes to us from a poem by Tang dynasty poet Meng Haoran (孟浩然, in Japanese Mou Kounen or Kouzen).
As you might expect, this phrase is only used in reference to the actual spring: it’s generally not going to be alluded to for regular sleeping-in at other times of year.
(“Shunmin akatsuki wo oboezu de, nando okoshite mo tsuma ga okinai.”)
[“Sleep in the springtime knows no dawn… so no matter how many times I try to wake my wife, she doesn’t actually wake up.”]