When the cherry blossoms fall, the people of Chichibu look down instead of up. On a hillside in Hitsujiyama Park, more than four hundred thousand plants of moss phlox — shibazakura, literally lawn cherry — cover the slope in a carpet of color. Ten varieties in pink and white and purple are planted together in patterns, so that the whole hill reads, from a distance, as a quilt of flowers.

Behind it rises Mount Buko, its face scarred pale by limestone quarrying. The contrast is the essence of Chichibu — the rough gray mountain above, the soft flowering carpet below, hardness and gentleness held in one view. This is a basin town, ringed by mountains, and the festival feels held by them.

The timing is deliberate, in its way. The moss phlox comes into its own just as the Somei-yoshino cherries finish, so that Chichibu's spring extends the season of blossom by turning it, quite literally, upside down. Where the cherry asks you to raise your eyes, the shibazakura asks you to lower them, to the ground blooming at your feet.

It runs from the start of April into early May, a month of flowers spread across a mountain valley. You come expecting a flower field and find, instead, an entire hillside remade — spring not overhead but underfoot, laid out to the horizon.