Crossword Genius

Extremist cultivated his veg (6)

Ross

I believe the answer is:

radish

'veg' is the definition.
(radish is a type of vegetable)

'extremist cultivated his' is the wordplay.
'extremist' becomes 'rad' (I've seen this in another clue).
'cultivated' is an anagram indicator.
'his' is an anagram of 'ish'.
'rad'+'ish'='RADISH'

(Other definitions for radish that I've seen before include "Red cold salad ingredient" , "Root vegetable used in salads" , "Hard vegetable" , "Daikon or mooli" , "Plant with crisp root eaten raw" .)

I've seen this clue in The Telegraph.
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