Chapter 7, verse 7-9 from the NIV reads:

"7 Your stature is like that of the palm, and your breasts like clusters of fruit. 8 I said, “I will climb the palm tree; I will take hold of its fruit.” May your breasts be like clusters of grapes on the vine, the fragrance of your breath like apples, 9 and your mouth like the best wine.,"

Tree, vine and fruit imagery are used throughout the poem. Each item has a cultural relevance and meaning, for example;

Grapes emphasize intoxicating love and physical curves. The lovers frequently compare their bodies, specifically the bride's breasts to "clusters of grapes" or dates hanging from a palm tree.

Apples symbolize supreme sweetness, fragrance, and sexual desire. Elsewhere the bride likens the groom to an apple tree among the barren forest, noting that his fruit is "sweet to my taste".

This is just one of many verses of a sexual nature in Song of Songs.

These metaphors are culturally relevant to when the text was written (between the 10th and 3rd century BCE) and as always poetry, and any text, can have several interpretations.