Kotohira is fine in any season but best in spring and autumn. Cherry blossoms line the steps to the shrine in late March and early April — sometimes coinciding with the Kanamaru-za kabuki festival, which is the busiest week of the year here and worth planning around even if you don't see a performance. Autumn brings red and yellow maples on the same path through November.
Summer in Shikoku is humid and hot; the climb up the steps in July or August is hard work. Winter is dry and clear with cold nights, and snow does occasionally dust the upper stages of the shrine, which is photogenic but slippery. The Reitaisai grand festival on 10 October is the shrine's most important annual ceremony, with portable shrines and elaborate ritual.