Is a black look one that grows red? (6)

I believe the answer is:

glower

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'black look one that grows red?' is the definition.
'glower' can be an answer for 'black look'. I'm unsure of the rest of the definition.

I don't understand the rest of the clue.

Can you help me to learn more?

(Other definitions for glower that I've seen before include "Stare angrily, scowl" , "firefly?" , "Glare" , "Look hard and angrily" , "Look hotly or angrily" .)

I've seen this clue in The Globe and Mail.

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