Most of my neighbors did not water their St. Augustine enough during the drought this past summer. Combined with the fall and winter that have been dry also, they may have lost large portions of their lawn. We do not have deep soil (pure limestone under the shallow topsoil) so we have to water a lot in my location. I have watered my St. Augustine during the fall and winter (not as much as in the summer). I hate to be pessimistic, but the reality is, the roots are pretty shallow as compared to bermuda grass. In the summmer, once the blades turn that weird dark green and start to wilt, the grass should be watered and not allowed to completely dry and turn whitish. Of course during the winter it does this as it goes dormant if it has been cold enough, but there should still be greenish stems under the dry blades. Check to see if there are any. Dig down and see if there are portions of the stems that are still greenish just below the soil surface. If you have some, there is still hope. If not, you may have a problem. You may have lost some of it in patches and you won't know until the weather warms up. If you lost just some in small areas, gently remove the dead blades and stems (thatch) with a rake so that the new blades receive sun and the runners can make contact with the soil. Given enough water ( flood it with water every few days until it starts to spread), it will spread to refill the area fairly quickly.
As stated above, plugging it is easier and cheaper than buying squares. But, you can buy squares and cut the squares up into smaller sections. If runners have grown into your flowerbeds, pull them along withe some roots and plant them in any dead areas. You wil be surpised how fast they grow. In sick looking areas, in the spring as the grass starts to sprout out, spread a thin layer of good, light, sandy loam topsoil that has been mixed with aged cow manure (nonhot). Check the topsoil by testing whether the clumps breakup easily when you squish them with your hand. If they don't, it has a lot of clay in it and will not be suitable for rejuvenating the grass. Or better yet, ask a local landscaping soil company if they have a living mulch that would be suitable for lawn rejuvenation. This will help the grass take off. You need to deep water it now if you haven't received much soaking rain. Do so every week if it doesn't rain. This will help the roots spread even though the grass is dormant.
I hope that not all of your grass has died.
