There is no word "grewed" in itself, because the past tense of grow is "grow". If the original text is written like this, we can understand it like this:

Greed is the variant past tense of greed, which means greed. The sentence that she stole the last orchid is enough to show her greed, so the variant of grewed, Grew is used to imply this greed. If it is a novel or other works, there may still be some artistic techniques.