How does Athol Fugard use imagery in Valley Song?

Fugard uses much creative imagery in the play and utilizes the technique of irony regarding the pivotal point where The Author makes his decision to buy the main house. Buks has been concerned for years that a new White man will buy the abandoned main house, forcing Buks and Veronica out of their little house, so it is ironic that the author decides to buy the house after a pleasant encounter with Buks and his overflowing wheelbarrow changes his previous decision not to purchase. "That wheelbarrow load of vegetables did it. I mean, come on now, how could I pass up the chance to own a piece of my native Karoo earth that would allow me to brag and boast about 'my own pumpkins,' 'my own beetroot,' 'my own potatoes."'