Perilla or "Shiso"

Hope you can answer this question regarding this plant that was given to me by a friend about two years ago... I was told it was purple basil, and when picked it really does smell and taste like basil, but when I looked it up in a book on herbs the only plant that looks like it is Perilla. And let me tell you it is quite invasive! It appears in places of the garden I did not intend it to be. I live in upstate New York the foothills of the Catskills, and from what I am reading it is an annual! Does this herb or whatever it is multiply, and come year after year stronger than ever?....

Purple Perilla is a herb that does look a lot like purple basil! But it does not taste all that much like basil... It has the cinnamon scent also found in basil and is used a lot in flavoring and coloring Japanese dishes.. We grow it in containers and never had it escape. There must be something that is just right for this herb in your garden and it therefore reproduces much more vigorously than normal there. I have the same problem with the greater celandine in my garden! If you wish to keep the plant to use it in oriental cooking I would suggest you make sure you do not let it go to seed. If this is too much vigilance for you, I can only recommend that you eradicate it in your garden and get some seed of purple basil instead.