The Butterfly iris (Dietes grandiflora) is native to southern Africa, which has a climate quite similar to our own here in San Diego, so they’re well-adapted to the dry climate and will thrive with only the smallest amount of water.
Beyond having really pretty flowers, they adapt well to sun or partial shade and have a compact (but tough) root structure can handle digging and re-planting with no ill effects. This make them a nice cover for areas that you know you’re going to have to dig up now and again.
This particular patch of butterfly iris has a dirty job to do. It provides cover for our drain cleanouts and septic tank lid. I think it’s doing it admirably.