Flower does go wild about the end of September (7)
I believe the answer is:
dogrose
'the end of september' is the definition.
I don't know anything about this answer so I can't judge whether this works.
'flower does go wild' is the wordplay.
'flower' becomes 'r' (abbreviation for river).
'wild' indicates anagramming the letters.
'r'+'does'+'go'='rdoesgo'
'rdoesgo' anagrammed gives 'DOGROSE'.
'about' is the link.
Can you help me to learn more?
(Another definition for dogrose that I've seen is " girl following track".)