What type of figurative language is two green thumbs that will grow into orange-yellow delights smelling summer?

The type of figurative language used in this phrase is a metaphor. A metaphor is a figure of speech that compares two unlike things, without using the words "like" or "as." In this case, the phrase "two green thumbs" is compared to "orange-yellow delights smelling summer." The comparison is between the person's ability to grow things (green thumbs) and the growth and smell of orange-yellow flowers in the summer.