That's more or less how I'd pronounce it, assuming that the plant is named after Perovskii, which would have to be Russian, and the emphasis would be on the -OV. But then, we would be calling Fuchsia "FOOK-si-yuh" instead of FEW-shuh, so using the pronunciation according to the name of the person honored isn't consistent in the United States. It would be that way in countries where they use a phonetic alphabet, like Russia, Spain or Germany, though.

I like what Allan Armitage has to say about it: Keep the syllables in the correct order, and have at it. My pronunciation skills are erratic at best, and this advice suits me to a T.