The poem "Digging" by Seamus Heaney is a relatively easy poem to talk about.
Two things are happening—first, the poet is at his desk, writing, pen in hand. He hears his father working outside the window, digging the the garden, among the flowerbeds. This brings him to a memory of his father working, digging potatoes. Then a second memory follows, of his grandfather working, how hard a worker he was, how he could stop for a minute to drink a bottle of milk, then immediately return to his work.
The poet then says that though he can deeply appreciate the work both his father and grandfather did, he himself can't do that same work.
"I’ve no spade to follow men like them."
But he can write.
"Between my finger and my thumb
The squat pen rests.
I’ll dig with it."
Each person has their own special gift, something they do well in their work. This is the main theme of the poem. "Digging" isn't a poem which is very hard to understand or needs to be overly analyzed. It speaks in plain terms of human lives, the purpose, dignity and value they have.