Hello to all...this is my first time on here initiating a post, but I have been reading from this site for about a year now. My question - does anyone in the PNW have experience with Japanese Blood Grass being invasive? I just put it into a planter 5'x6' and 1' high (bottom open to ground) with a spirea and dward cedar and am wondering if this is a mistake. Any opinions on this are very much appreciated. Thanks.