Flower in beer garden's half gone to seed (7)
I believe the answer is:
gerbera
'seed' is the definition.
The answer and definition can be both plants as well as being singular nouns.
Perhaps you can see an association between them that I can't see?
'flower in beer garden's half gone' is the wordplay.
'flower in beer garden's' becomes 'gerbe' (I can't justify this - if you can you should give a lot more credence to this answer).
'half' indicates taking half.
'gone' becomes 'rang' (ringing is a kind of going).
'rang' cut in half is 'ra'.
'gerbe'+'ra'='GERBERA'
'to' acts as a link.
Can you help me to learn more?
(Other definitions for gerbera that I've seen before include "Coloured daisy-like flower" , "Barberton daisy" , "something in the garden" , "Bright daisy-like plant" , "Plant with brightly coloured flowers" .)