啓 means "to open," 蟄 means "hidden away" or "in hibernation" — this kō's own title is the direct mirror image of #47, 蟄虫坏戸 (Mushi kakurete to o fusagu, "insects hide away and close their doors"), written five and a half months and forty kō earlier at the start of autumn. Where that kō sealed the door, this one opens it: 蟄虫 stands for every creature that spent winter dormant underground, not literally just insects, all of them now stirring back into activity as the soil genuinely warms.
Traditional belief credited the season's first thunder with actually startling these creatures awake — 虫出しの雷 (mushidashi no kaminari, "the thunder that brings the insects out"), a spring thunderclap treated as a welcome, almost celebratory sound rather than simply a weather event, precisely because of what it was thought to trigger underground.
At its best through this stretch of spring.
Still in good season, mild and flaky.
Sweet and juicy, in season through March.
A crisp, mildly aromatic stalk vegetable coming into season now, good raw with a vinegar-miso dressing or lightly cooked.
Still at its best.
Boke's dense, waxy red or white blossoms cling directly to bare, thorny branches with almost no stem — an unusually sturdy-looking flower for how early in spring it commits to blooming.
The first thunder of the year, generally heard sometime around Keichitsu, carried a specific folk meaning beyond just marking a change in weather: the noise itself was believed to startle hibernating creatures out of the ground, hence the name. Unlike summer thunder, which mostly reads as simply dramatic or threatening, this particular clap was treated as a genuinely good omen — proof that the season had turned decisively enough for the sky itself to announce it.
"The mountain laughs" — One of four seasonal mountain-images drawn from a phrase attributed to the Northern Song painter Guo Xi (郭熙), recorded by his son: mountains "laugh" in spring as fresh green returns, "drip" (山滴る) in summer's lush wet growth, "dress up" (山粧う) in autumn color, and "sleep" (山眠る) under winter's bare stillness — a full cycle of personification that entered Japanese haiku vocabulary by the Edo period and has stayed there since.
蟄 pairs directly with 坏 (or 閉) across the calendar's two matched kō — 蟄虫坏戸 in early autumn closes the door, 蟄虫啓戸 here in early spring opens it, the same underlying image of hibernation held at both ends of its full five-and-a-half-month arc.
A small shift in how an ordinary weather event registers, worth trying even briefly.
Its flowers commit early and fully, often before much else nearby has opened at all.
The outer layer is fibrous and bitter; a thick peel reveals the crisp, milder flesh underneath.
This kō's subject isn't metaphorical — actual insect life picks up noticeably from this point in the calendar onward.
This kō's whole claim is that something was never actually gone, only closed off and waiting — the same creatures, the same soil, simply sealed for a season and now reopening rather than starting over from nothing. That's a different, gentler shape than starting fresh: less like being reborn, more like being let back in. What door in your own life has been shut for a while now, not destroyed, just closed — and what would it take to actually open it again?