If a plot's full of holes, this may have something to do with it (6)
I believe the answer is:
trowel
'if a plot's full of holes this may have something to do' is the definition.
Although both the answer and definition are singular nouns, I don't understand how they can define each other.
'it' is the wordplay.
I cannot quite understand how this works, but
'it' could be 't' (abbreviation. e.g. in 'tis) and 't' is present in the answer.
The remaining letters 'rowel' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
'with' is the link.
Can you help me to learn more?
(Other definitions for trowel that I've seen before include "Small hand tool for gardening" , "Something to help gardener" , "Small spade" , "Small hand tool for garden" , "Spreading implement" .)