There is a little ground cover known as Perennial Peanut. It is a thick low growing replacement for any lawn especially St. Augustine. You see, St. Augustine is a water hog, when St Augustine gets just a little dry, its immune system is weakened, it thins out and bugs and fungi move in. The scenario is that you spend a lot of money replacing it and then in two or three years the St. Augustine declines again. At some point this can become expensive. Perennial peanut may be the answer.
It is drought tolerant and with water restrictions becoming more prevalent, we really need to be thinking about economical and low maintenance ways to keep a good looking landscape. Re if you like it or not, you could try a sample by planting the median strip in front of your house first. If you don't want to go to that extent, just try one or two plants in another area of the yard but please be well aware that it will grow into the other plants, so normally we will not plan it within a bed, but this is only for the purposes to quickly see it will do well for you and to make sure that it's look appeals to you.
This plant will not freeze but certainly will not be as lush in the Winter as it will be the rest of year. It works well too in dryer soils and it totally insect resistant. I like it so much I am using it in parts of my yard.
A shameless plug by the way, If you are interested in purchasing this beautiful plant, just call us at Sims Landscaping and we can order it in large quantities. The number (352) 383-3303.