The Day Job,
This review is from: The Day Job: Adventures of a Jobbing Gardener (Paperback)
"The Day Job" won't teach you anything about gardening except, perhaps, that castor oil keeps moles on the move (as well as humans).
It is, though, a highly entertaining description of the mixed bouquet of people, rich and poor, who need the services of a gardener.
As with all Mark's other books, you just don't want it to end.