Cultivate ebony as cash crop (3,4)

I believe the answer is:

soy bean

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'cultivate ebony as cash crop' is the definition.
I know nothing about this answer so I can't tell whether it can be defined by this definition.

'cultivate ebony as cash crop' is the wordplay.
'cultivate' indicates anagramming the letters (I've seen 'cultivated' mean this).
'cash' becomes 'p' (abbreviation for pence).
'crop' means to remove the last letter.
'ebony'+'as'+'p'='ebonyasp'
'ebonyasp' with its last letter removed is 'ebonyas'.
'ebonyas' anagrammed gives 'SOY BEAN'.

Can you help me to learn more?

(Another definition for soy bean that I've seen is " Source of oil".)

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