Hello,
The Label for this product unfortunately does not include edible plants and is instead intended for houseplants, therefore this product should not have been recommended for use in your situation. If the product was labeled for citrus it would list it as an acceptable crop, give instructions for the amount to apply for that use, and then it would describe how much prior to harvest it would need to be applied so that the food could be consumed safely. Your label does not have this since citrus is not a crop covered by this label. The active ingredient imidacloprid can stay active in a plant for a year or more, and without specific label information I cannot give an amount of time when the fruit could be consumed. 

I am sorry I don't have a better answer for you, but I am glad you reached out for more information before consuming the fruit.
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