The Oscar-winning actress - who lives with husband Keith Urban and their two-year-old daughter Sunday Rose in Nashville, Tennessee - is said to spend hours tending to her garden so she can feed her family home-grown, organic produce.
A friend of the star told the National Enquirer magazine: "She likes to have fresh organic produce for their daughter, Sunday. She doesn`t mind getting her hands dirty to make sure that the lettuce and corn come out perfectly."
In addition to growing vegetables at her home, Nicole recently revealed she has fulfilled a lifelong ambition by raising alpacas in her garden.
She explained: "We just planted our vegetables for the summer. I`m hoping the corn will be beautiful, because I love eating corn out of the garden.
"And we just bought some alpacas. They are sort of the cousins of llamas, which I`ve always wanted because of their long necks and eyelashes."