Gold initially buried under garden soil (6)
I believe the answer is:
bedaub
'soil' is the definition.
(thesaurus)
'gold initially buried under garden' is the wordplay.
'gold' becomes 'au' (Au is the chemical symbol for gold).
'initially' suggests taking the first letters.
'under' means one lot of letters go next to another.
'garden' becomes 'bed' (I've seen this in other clues).
The first letter of 'buried' is 'b'.
'au'+'b'='aub'
'aub' after 'bed' is 'BEDAUB'.
(Other definitions for bedaub that I've seen before include "Smear (with a sticky substance)" , "Splodge with paint" , "Crudely paint" , "Smear with something sticky" .)