Expert in garden centre didn't linger (5)
I believe the answer is:
raced
'didn't linger' is the definition.
I can't judge whether this definition defines the answer.
'expert in garden centre' is the wordplay.
'expert' becomes 'ace' (ace can informally mean very good).
'in' indicates putting letters inside.
'centre' means to look at the middle letters.
The middle letters of 'garden' are 'rd'.
'ace' placed inside 'rd' is 'RACED'.
Can you help me to learn more?
(Other definitions for raced that I've seen before include "Ran competitively" , "Competed" , "Dashed" , "Rushed" , "Ran fast" .)