Instils gardenia to get a marinade for a salad (7,8)

I believe the answer is:

italian dressing

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'instils gardenia to get a marinade for a salad' is the definition.
I can't tell whether this defines the answer.

'instils gardenia to get a marinade for a salad' is the wordplay.
'instils gardenia' can be anagrammed to 'ITALIAN DRESSING'.
But, I am not clear how the anagram is indicated.

Can you help me to learn more?

I've seen this clue in the Sydney Morning Herald.

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