One who grows red with anger, perhaps (8)
I believe the answer is:
gardener
'one who grows' is the definition.
The answer is a person as well as being a singular noun. This is suggested by the definition.
'red with anger perhaps' is the wordplay.
'with' says to put letters next to each other.
'perhaps' is an anagram indicator.
'red' put after 'anger' is 'angerred'.
'angerred' anagrammed gives 'GARDENER'.
Can you help me to learn more?
(Other definitions for gardener that I've seen before include "Eg, Capability Brown" , "someone in bed" , "Jesus was mistaken for" , "He tends flowers and shrubs" , "Red anger of an outdoor worker" .)