Dick sticks with garden implement (7)
I believe the answer is:
gumshoe
'dick' is the definition.
(I know that dick can be written as gumshoe)
'sticks with garden implement' is the wordplay.
'sticks' becomes 'gums'.
'with' is a charade indicator (letters next to each other).
'garden implement' becomes 'hoe' (tool used when gardening).
'gums'+'hoe'='GUMSHOE'
(Other definitions for gumshoe that I've seen before include "Possible US version of Morse" , "Galosh - sleuth" , "Foreign investigator" , "Dick" , "Detective (US colloq.)" .)