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“If you have an old tree in your garden with a knothole or hollow in it, you are very lucky! This is a fairy mailbox and, for hundreds of years, people have used these to communicate wishes to the fairies. On a new moon, write a short letter with your wish on a small piece of paper. Place a flower in it and put it in the hollow. By the full moon, they should give you an answer!.”

–The Magical Garden: Spells, Charms, and Lore for Magical Gardens and the Curious Gardeners Who Tend Them by Sophia Sargent