Passion in forest, city wanting it (7)
I believe the answer is:
Here is my best explanation:
'passion' is the definition.
'forest city wanting it' is the subsidiary indication.
'forest' becomes 'arden'.
'wanting' suggests deleting specific letters (to want something can mean to lack it or need it).
'city' with 'it' removed is 'cy'.
'in' is the link.