What is the theme in The Underground Gardens by T. Coraghessan Boyle?

Faith is a major theme. While "The Underground Gardens" explores many ideas, the common thread that runs through the story is faith—namely, Baldasare's near-unshakeable faith in his ability to achieve his dreams. "He'd always thought big, even when he was a boy wandering his father's orchards." Recognizing early on that his place in the family assured he would never inherit these orchards, "Baldasare wasn't discouraged—he knew he was destined for greatness." Baldasare initially thinks this greatness will come in a familiar form, as the owner of his own vineyards inAmerica.