check out the farm where you find Dolly (in between Roma, Forest, Graveyard, and Desert) then look in between the crops for the flowers :)
from left to right the first flower is blue in the first column, so blue equals 1, pink is in the third, orange 5th, white 7th. so the numbers for the code are 1 3 7 5. i already opened the box so i don't remember the color order. i'm also not sure if the road counts as column, so pink and orange might be +1