Border in small church plot (6)
I believe the answer is:
scheme
'plot' is the definition.
(scheming is a kind of plotting)
'border in small church' is the wordplay.
'border' becomes 'hem' (I've seen this before).
'in' indicates putting letters inside.
'small' becomes 's' (abbreviation - e.g. clothes size).
'church' becomes 'ce' (abbreviation for Church of England).
's'+'ce'='sce'
'hem' placed into 'sce' is 'SCHEME'.
(Other definitions for scheme that I've seen before include "Systematic plan or arrangement" , "Program" , "Hatch - plot" , "proposal" , "Cunning plan" .)