Growing source of food and drink (7)
I believe the answer is:
coconut
'drink' is the definition.
The answer and definition can be both things that one consumes for nourishment as well as being singular nouns.
Perhaps they are linked in a way I don't understand?
'growing source of food' is the wordplay.
'growing source of' becomes 'coco' (I can't justify this - if you can you should give a lot more credence to this answer).
'food' becomes 'nut' (I have seen 'Vegetarian food' mean 'nut' so perhaps 'food' could also mean 'nut').
'coco'+'nut'='COCONUT'
'and' acts as a link.
Can you help me to learn more?
(Other definitions for coconut that I've seen before include "Large palm fruit" , "Seed of a tropical palm" , "Hard thing" , "that's hairy and tough!" , "Large seed; head" .)