A difficult mystery:) A similar shot could have been taken in fall, winter and spring. Winter is the least likely - although I remember one winter when the grass was bright green all December and snow fell in mid-January. No leaves on the trees at all - that's more for spring, in fall a little foliage is usually left But the flowers in the flowerbeds are a very serious argument in favor of autumn, late fall flowers can be seen even in November. People are dressed lightly, not a single person in a down jacket - this is also for fall, in spring some people are in no hurry to get out of winter clothes. So it's still fall - either the photographer caught the moment and made a shot that doesn't correspond to the season:)