Dont know what flowering plants wont need deadheaded at least once but how bout the following all under a foot, evergreen and tolerate of drought once established (all plants drought tolerate or not need regular watering at least thru 1st season)

creeping sedums, Hens-n-Chicks, creeping thymes....there literally so many different creeping sedums to choose from...I have 5 types, with different leaf shapes, color, and habit, flower, etc, some turn purple in late fall/winter and green up again in spring..several H&C's are available also. There are both flowering and non-flowering creeping thymes. If you want a low growing ornamental clump forming grass that likes a dry condition try Blue Fescue's...I'd say mine grow between 10" to 14" and gives a feathery/vertical look for the low growing plants above...

It's early morn and I'm stuck trying to think of other's!
Hope this is a start to help you choose :)

Vera