"Bladet er helt gult om efteråret."
Translation:The leaf is entirely yellow in the fall.
I have a problem with with DL not accepting in autumn, in winter, in spring, in summer as English translations where other languages do have the definite article in front of the season.
I agree. If we learn that 'i sommeren' means 'in the summer' then naturally when we want to write 'in summer' we will write 'i sommer' and it will be wrong. We need to be told what it actually means, not the literal translation, or we will not understand how Danes use the words in real life.