There is a hedge-maze in the Horse-fields at the Spring Planting in Bree, and Sorrel North-took wants you to talk to her sister Buttercup before you partake in the aimless adventure.
NOTE: This quest will be removed from your quest log when the current festival ends.
'Hi! You there, young ${RACE}! Have you seen the hedge maze yet? Half the attendants of the Feast of the Greenfields seem to have gone off to the maze in Bree. If you find yourself there this spring, you must talk to my dear sister Buttercup, who went on a great journey to see the hedges. She has always been most fond of foliage.
'It sounds like there is a great deal of fun to be had on the Horse-fields this year. I know you'll find yourself there before the festival is done with -- you must give my regards to Buttercup while she is there!'
Buttercup North-took is at the Festival Grounds in Bree, enjoying the hedge-maze on the Horse-fields.
You should make your way to the maze to give Sorrel's regards to her sister Buttercup.