Fatherly flower? (5)

I believe the answer is:

poppy

I'm a little stuck... Click here to teach me more about this clue!

'flower?' is the definition.
(I know that poppy is a type of flower)

I don't understand the remainder of the clue.

(Other definitions for poppy that I've seen before include "Flander's flower" , "Bright red flower, source of opium" , "Red field flower" , "Red wild flower" , "Cornfield plant" .)

I've seen this clue in the Evening Standard.

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