Man himself is the tree of desire, and the root of that tree is in his own heart.

Bowl of Saki, by Hazrat Inayat Khan:

In the traditions of the Hindus there is a well-known idea: that of the tree of the fulfillment of desires. There is a story in India of a man who was told that there was a tree of the fulfillment of desires, and who went in search of it. After going through the forests and across the mountains he arrived at last at a place where he lay down and slept without knowing that the tree of the fulfillment of desires was there. Before he went to sleep he was so tired that he thought, 'What a good thing it would be if I had just now a soft bed to rest upon and a beautiful house with a courtyard around it and a fountain, and people waiting on me!' With this thought he went to sleep, and when he opened his eyes from sleep he saw that he was lying in a soft bed, and there was a beautiful house and a courtyard and a fountain, and there were people waiting on him. He was very much astonished and remembered that before going to sleep he had thought about this subject, he found, 'The tree that I was looking for it was under that tree that I slept, and it was the miracle of the tree that was accomplished.'
The interpretation of this legend is a philosophy in itself. It is man himself who is the tree of fulfillment of his desire, and the root of this tree is in the heart of man.
There are dead thoughts, and there are living thoughts. To which class a thought belongs depends on the power called will power. When there is will power, the word is both spoken and done.
This idea is expressed by the words Kalpa-Vriksha, the tree of desire. The story is that whoever happens to sit down for a moment under this tree will have his wish fulfilled; yet nobody knows where this tree is to be found. The tree is the mind; its root is the heart. That which gives power to thought, gives spirit or life to thought, is feeling. A man without feeling is as though dead; with feeling he is living, and so is his thought. Thought with feeling is a much greater power than thought without feeling. Merely to say, 'I like your picture so much' will have no effect when there is no feeling behind it. It is just a string of words. There is no life in it. But when these words are uttered with feeling they go through your heart also; the thought becomes living.