In Mexico, horticulturalists are a group of people with something in common (6)
I believe the answer is:
cohort
'a group of people with something in common' is the definition.
I can't judge whether this defines the answer.
'in mexico horticulturalists are' is the wordplay.
'in' says the answer is hidden in the clue.
'COHORT' can be found hidden inside 'mexico horticulturalists are'.
Can you help me to learn more?
(Other definitions for cohort that I've seen before include "Warrior band (orig. legion section)" , "Band of fighters" , "Group of people with a shared characteristic, age say" , "One tenth of a Roman legion" , "One of ten in a Roman Legion" .)