Groundcover between stepping stones
I have about ten round stepping stones that were set in concrete/cement by the original owners of our house. They are set in a semi-circular pattern coming from my deck step: 4, then 3, 2, then 1.
I have a problem with grass sporadically growing in between these stones and last year wanted to tuck creeping thyme in between them. I didn't know the true depth of the soil, nor did I know the stones were set in cement until I actually began to plant the thyme. There is approximately 1" of soil.
Last year I didn't plant it at the best time; I waited until the end of June/first of July, and with our drought it didn't survive. I tried to water it on our alotted days. Was the possible reason for it not surviving because of the drought, the shade in which the stones are placed, or the lack of depth in the soil?
Is there any other creeping ground cover that would survive these circumstances?