In spring, I believe it filled with birdsong and blossoms, so I placed colorful trees to make the farm full of vitality
For summer, my initial impression was that it's particularly hot. I wanted to include red fireflies to represent the heat, but I found that red didn't go well with green. Ultimately, I changed it to gold and green.
Generally, autumn is associated with wheat and falling leaves, both of golden. So, I built an autumn farm with golden theme.
And about the winter, its cold. However, I thought the animals would need warmth because its a farm. So, I placed golden fireflies and a bonfire in the white scenes, make winter look less cold.