One literary device in Seamus Heaney's poem “Blackberry-Picking” is imagery. In each of the two stanzas, Heaney provides vivid pictures of the blackberries. In the third line, Heaney describes the blackberries as a “glossy purple clot.” In the next line, he says they’re “red, green, hard as a knot.” The detailed presentation of the blackberries could help one acquire an acute sense of the fruit's texture, look, and feel. Through the nuanced imagery, one might feel as if they’re handling the blackberries themselves.
Some of the imagery contains other literary devices. Go back to the “hard as a knot” image. This image is produced via simile. Heaney uses the simile literary device to compare the blackberries to something else—a knot. Such associations could help one look at the blackberries in new and imaginative ways. In the sixth line of the poem, Heaney uses a simile to link the blackberries to “thickened wine.” In the penultimate line of the first stanza, Heaney likens the blackberries to a somewhat macabre “plate of eyes.”
A third literary device used in the poem is alliteration. At select points in the poem, Heaney strings together words that start with the same letter. For example, in the fourteenth line of the poem, Heaney notes how the “big dark blobs burned.” The proximity of the three b words results in alliteration and brings a melodic quality to the poem.