Grows flowers, but not the first one (5)
I believe the answer is:
rises
'grows' is the definition.
(rise can mean to grow or increase)
'flowers but not the first one' is the wordplay.
'flowers' becomes 'irises' (type of flower).
'but not the first one' means to remove the first letter.
'irises' with its initial letter taken off is 'RISES'.
(Other definitions for rises that I've seen before include "Comes or goes upward" , "Moves upward" , "Gets up" , "Moves upwards" , "Ascends" .)