Alpinia

Worrying isn't it? I know that certain Hedychium species have become major pests outside their native range. I guess these began as ornamentals but have found the conditions outside the garden to their liking.

Thank you, Craig. I thought it could be a Zingiberaceae, but I wasn't sure. I am amazed to see how many plants of this family are growing wild or semi-wild in my area. I hope this doesn't become a problem in the future.