Check out these graceful, edgy planters from Planterworx. Today, Fab.com (yeah, you need to register before you can shop) has a special price on these recycled steel planters. They are handmade in Brooklyn and would be great for a modernist gardener who wants a lot of impact with a minimal amount of plants. Just watch the weight!
Round out the modern look with Zuo Outdoor, also at Fab.com.