One of the most obvious examples of imagery in The Vagabond is:
Biting the blue finger
In this part of the poem, it is Autumn and frosts are becoming common. The 'blue finger' could represent either the man's hands turning blue with cold (circulation is not as efficient to the extremities in cooler weather).
Or it could represent the plant 'blue finger', common to South Africa. This interpretation would then link into the next line, where the fields are covered in 'biting' frost.
white as meal
This is a simile--a type of metaphor which uses 'like' or 'as'. Here, the fields are frosty, looking like they've been 'dusted' with flour (meal).
warm the fireside haven
In complete contrast to the icy, frosty conditions of the lines above, this line invokes a completely different imagery. You immediately imagine a roaring fire, maybe an arm-chair, a book and a hot drink. This 'haven' is probably, in real life, a small camp-fire--wind whipped and requiring constant attention. But to the speaker, it is as if they are safe (and inside).