This book is just charming. It reminds me of Shannon Hale's Goose Girl and
Jessica Day George's Dragon Slippers and that's good company to be in.
It's a lovely story of a humble princess who doesn't want all that goes with being royalty and finds an unexpected friend in a close-to-her-own-age common gardener. Of course, Gavin turns out to be more than a friend and there in lies the difficulty. Royals and commoners don't mix.
Lots of twists and turns in this book, plus kisses, villains, marriages, breaking the rules, etc.
Well told, well developed, and easy to fall right into the lives and hearts of the characters.
For a lovely tale of old that just makes you breath a delighted sigh when it's over, pick up Just Ella by Annette K. Larsen.