Source of fruit or beet (7)
I believe the answer is:
orchard
'source of fruit' is the definition.
(I've seen this before)
'or beet' is the wordplay.
'beet' becomes 'chard' (chard is a kind of beet).
'or'+'chard'='ORCHARD'
(Other definitions for orchard that I've seen before include "Field for growing fruit" , "One may grow fruit" , "Fruit-growing area" , "Small wood of fruit trees" , "where fruit trees grow" .)