m0useanswered grow question 13h ago That's the smiley face indicator of the diary. its like a traffic light Red Yellow Green.
Green being good and happy,
Yellow being mid/ok
Red being bad/needs improvement.
Like others said it gets more green the more information you add to the diary. Some times you just need to add more lines of text to the body of the diary to get that section green. Or add a few more photos. They use this colour system for the headers of each category in the diary update process and harvest reports.