Spread debris everywhere, perhaps - clean up with time (5)
I believe the answer is:
erupt
'spread debris everywhere' is the definition.
I can't judge whether this definition defines the answer.
'clean up with time' is the wordplay.
'clean' becomes 'pure' (similar in meaning).
'up' says the letters should be written backwards (in down clue: letters go upwards).
'with' means one lot of letters go next to another.
'time' becomes 't' (abbreviation).
'pure' backwards is 'erup'.
'erup'+'t'='ERUPT'
'perhaps' is the link.
Can you help me to learn more?
(Other definitions for erupt that I've seen before include "Explode" , "suddenly burst out" , "Burst forth violently" , "Break through (as a volcano)" , "Break out suddenly and violently" .)