I have been planting OGs in the two planters that frame my front door for the past few years. I love the look of the grasses, but sometimes they arch over their containers and block access to the doorway. I'm now looking for varities that are a more columnar, upright style than the arching style I've been using in the past. I know that Calamagrostis "Karl Forster" is a good choice in this regard, but I was hoping to find a few other varieties to choose from. I'm open to either annuals or perennials. Thanks for any ideas!