A blaze of second colour finally from popular green plant (7)
I believe the answer is:
inferno
'a blaze' is the definition.
(I've seen this before)
'second colour finally from popular green plant' is the wordplay.
'second colour' becomes 'o' (end letter of 'colour').
'finally' says to put letters next to each other (some letters go at the end of others).
'from' becomes 'in' (I've seen this in other clues).
'popular green plant' becomes 'fern' (I can't explain this - if you can you should believe this answer much more).
'in'+'fern'='infern'
'o' after 'infern' is 'INFERNO'.
'of' is the link.
Can you help me to learn more?
(Other definitions for inferno that I've seen before include "Fierce fire" , "(Hellish) blaze" , "A raging fire as in hell - ask Dante" , "Uncontrollable fire" , "Large uncontrolled fire" .)