We've just moved into our first home - and I had my heart set on moving my herb garden to windoxboxes suspended from our rear deck (a small stairway/landing leading to a patio). Trouble is, the deck is Trex material - can't use the regular screws/bolts that come with the "universal" windowbox bracket found at Home Depot and the like.

Are there supports/brackets out there that are no-screw installation, but can fit on a wide trex railing? Thanks!