I've long been a fan of Sedums, but it wasn't until I ventured beyond the tallish 'Sedum Joy' and its ilk and tried groundcover-height Sedums that I became an ardent fan. In fact I'm quite the proselytizer, touting its virtues as a replacement for turfgrass on sunny sites like the one below.
This groundcover Sedum (S. sarmentosum, linare or acre, depending on the source) quickly filled in my former 1,000-square foot lawn. It's thick enough to keep weed seeds that land on it from germinating. So, no weeding required. It's short enough (about three inches) to never need mowing. And like all Sedums, it needs no fertilizing and after its first week or so in the ground, no more watering. Because Sedums are succulents, holding moisture in their thick leaves, they're super-drought-tolerant, almost as much so as cacti.
No wonder they're the preferred plant for green roofs, like the one below.
Sedum can even withstand a bit of foot traffic. When used to cover a large area, mine had to be stepped on in the fall for me to clean up leaves and other debris, and within a day or two it always bounced right back.
I thought it was strange that such beautiful, almost-no-maintenance plants were so little used down on the ground, not just on roofs where they're ubiquitous, but finally just last year I started seeing them used as groundcovers in public gardens, like the U.S. Botanic Gardens.
Above you see the vigorous 'Angelina' variety of Sedum as groundcover in their rose garden, and it looks fabulous even here on April 1, before the new season's foliage had appeared. At the very top of this post is a scene from the rose garden as it looks in mid-May, with two more Sedums used as groundcover.
The USBG's rose garden is outstanding not just for its smart use of groundcovers and the beauty of its roses but also for its use of absolutely no pesticides. If a rose gets disease or too much insect damage, the rosarian-in-charge just pitches it and then tries another. She also uses signage to help educate visitors to the wealth of roses that WILL grow here in the Humidity Belt without the need for spraying of any kind.
I think these super-short Sedums are especially useful beneath roses because unlike other traditional perennials mixed with roses - Lavender or Nepeta, for example - the Sedum never interferes with the good air circulation so necessary to prevent fungal disease. It's also too short to shade the roses.
Here's a couple of close-ups of the USBG's groundcover Sedums. On the left is 'Angelina' and on the right is Sedum kamtschaticum, though there are many Sedum varieties with similar foliage and blooms, so I could be wrong.
Finally, here's a scene I noticed at Longwood Gardens when I visited last week, with the ever-popular 'Angelina' again.