Vinca major and minor work well for me.Asiatic jasmine in mass plantings.

You can't go wrong with sedum (stonecrop); comes in all sizes and colors.

Geranium sanguineum "Striata" is a good one.

Creeping Thyme is the toughest ground cover I have come across. It laughs at drought.

Is creeping thyme the same as the herb? I can't seem to find it.

Try some Diascia and Salvia Wild Thing as well as Agastache and Caryopteris. The Diascia are low growing and have almost constant bloom The same is true of the others though they grow taller. A great source is High Country Gardens.

Any difference between creeping thyme and wooly thyme?

I agree with the stonecrop sedums. Virtually indestructible..

Artemisia "Silver Brocade" (beach wormwood). I set out three new plants this spring, and they received only what water fell from the sky in May and June, after their initial drench from the watering can. They have filled out and spread nicely. Regarding thyme, it is the same of the herb; there are low-growing types and more upright types. Read label descriptions. Vinca minor needs watering until it's well established, which takes at least 1-2 years. If you have a spot where nothing will grow, English ivy and goutweed will--but don't try to grow anything else there, and keep an eye on the perimeter! In dry shade, lamium maculatum (I have "White Nancy") will get along pretty well, and if it gets droopy can be easily revived.

There are several creeping thyme's and the wooly kind is among them. I've had some success with it, but in general, I plant enought other perrenials that a groundcover would be redundant.

Lamb's Ears! You can hardly kill the stuff! Also Fringed Sage, but it is not as thick as lambs ears.

Fireraven9
Fairest of the months! Ripe summer's queen
The hey-day of the year
With robes that gleam with sunny sheen
Sweet August doth appear. -Â Â R. Combe Miller

If you're looking for drought tolerant groundcovers, try this site.

Newt

Here is a link that might be useful: Stepables

I kept creeping tyme green through Tucson's record summer with over 100 days with out rain. Wexey

Symphytum grandiflorum is sometimes called Dwarf Comfrey. Is this what you are looking for? Or do you need a variety of S officinale?

I have a dwarf pennyroyaln(prostrate to the max!)as well as wooley thyme that are both hangin' in there among the flagstones. To Angie in Tampa: there are several creeping thymes, including mother-of-thyme and wooley, neither are the same as the culinary thyme you are likely familiar with. Check richters.com for a long list. CK

cotoneaster once established

aloe vera or medicine plant , prickly pear cactus (fruit strain ) there is also a Galopagos strain that is taller.
jojoba prized for its oil, will grow in desert conditions.
other possibilities that might work but might not: beach plums (the plums are the size of a nickel and have stones they are a low shrub) , bilboa tree from Africa , eucaliptus from Austrailia, monkey puzzel tree Patagonia ,
peach , almond . the most drought resistant corn is an american Indian strain sold by www.nativeseedsearch.org but i don't remember the strain. read up on deserts around the world and keep us posted on what you find . The most arid desert is in South America Argentina I think . check "xeroscape"

desert chia from www.nativeseedsearch.org

I am in Zone 5 but I have been researching the heck out of ground covering lately. It has become an additive behaviour to be honest. After much reserach I determined that one of the hardiest groundcovering is the VINCA MINOR/ Periwinkle. I bought some from the Home Depot that was already potted. But then I realized that even at a couple of $$$ it can get expensive fast. So guess what I did believe it or not..... I hit EBAY and plugged in Vinca Minor just for the heck of it.

One of the many store advertised on Ebay had the best offer I had yet to see on line much less than Jackson & Perkins and other web stores).... Vinca Minor 250 roots for $12.49. YES you heard me 250 vinca roots grown in the field will be sealed, packaged safely and mailed to me for about $13 (gotta hold off on the Starbucks for the day..lol). As a matter of fact I ordered a total of 500 to split with mom. We plan to use them as LAWN SUBSTITUTES. I have a tree with outgrowing roots that will not allow grass to grow. So now I am forced to have a perrenial groundcovering.

I say all this to say go for it! Try the vinca minor, get the best price (don't overlook ebay stores), and plant away. Other good websites were: classygroundcovers.com; wilsonbrosnursey.com; michiganbulbs.com, dutchgardens.com; blueskynursery.com, plantdelights.com, waltersgardens.com, northbranchnursery.com; gardenheights.com; jacksonandperkins.com; colorscapesgreenhouse.com

Another way is just plug in the question and just see what pops up.

Wish me luck with the vinca minor/periwinkle and keep me posted on your status.