Hmmmm... I was going to say you weren't watering enough. Three intervals of three minutes isn't very much. And in 100 degree temps, I'd say what little bit of water that's being applied is evaporating very quickly. But after after backing off you're finding the worst areas are still "WET" and in poor-draining, heavily-shaded spots, you've probably overwatered those areas. I'd continue to keep watering as you currently are. Good job waiting until you see signs of wilting. But I'd also only hand-water those areas that are showing signs of wilting. Hold off on the poor-draining, well-shaded areas until they start to wilt. The good news is that if your patches of brown aren't too large, the St. A will fill it in rather quickly once you get your watering dialed in. (I had a 10' diameter bare patch where the kids' pool was last year that filled in in about 8 weeks this spring.)

Well, you have been getting advice that conflicts with what we have learned here over the years. You say you want to do everything right. Here are the lessons learned from years of reading Internet gardening forums. 1. NEVER rototill in preparation for laying seed or sod. 2. You can sod any day of the year. 3. Palmetto is a relatively poor variety. Floratam is the one you really want. So that bad news is that you wasted time and money preparing the soil. The good news is you can still have the best looking lawn in the neighborhood starting from where you are. Before the sod arrives, go out and water the soil completely. Water for at least an hour. This will settle the soil that is currently fluffy. After the soil settles some, level it again using a rake or filling in with sand/soil. Try not to raise the surface of the soil by blanket top dressing. All you want to do is fill the holes. Then water it again to settle the new surface. You can get the most level surface by dragging a piece of weighted chain link fence over the soil. That tool will loosen the high spots and drag high soil into the low spots that you cannot see. Then after your sod goes down, rent a water fillable roller to push the sod down to the surface of the soil. Roots from the sod will not grow through the air to reach the soil. The sod has to be touching everywhere. Since you cannot afford a sprinkler, go to Home Depot and get a Vigoro water hose timer. Then get as many oscillating sprinklers as you need to cover your lawn all at the same time. Then go to Sears and get Craftsman brand hoses to connect to the timer and the sprinklers (Sears' hoses do not leak at the fittings if you tighten them properly). You might need splitters to feed all the hoses out of the timer. I like the big green and black ones from Lowe's. Set your timer to go off every day, morning, noon, and night, for 10 minutes each time. You need to do this so the sod will knit to the underlying soil. If you do this for three weeks, the roots will be in and you're off to the races. After the roots are in you can back off on the watering. Ultimately you want to back off to watering once every week in the summer heat and once or twice a month the rest of the year. Use your timer to do this. I was going to lose my lawn this year until I got the timer rigged up. Mulch mow St Augustine at the mower's highest setting. Weld the adjusters in place so that your well meaning brother in law doesn't come by some day to do you a favor and he scalps your nice lawn. St Aug never needs to be scalped. Just mowing at the highest setting will give you the best looking lawn in the neighborhood. I fertilize with organic fertilizer 5 times per year on the federal holidays. I start on Washington's Birthday and end on Thanksgiving. If you use synthetic you can follow the same schedule except skip 4th of July...and also don't do the first one until after you have mowed real grass for the second time in the spring. If you don't want to spend the money on new hoses, cut the male ends of your current hoses off and replace them with the black plastic repair ends from Lowe's. The stamped brass fittings are the worst. The Sears brass fittings are slightly better. I really prefer the black plastic male fittings for all my hoses. They seal tight every time.

Wish I had more info for you since your plan sounds much better than a toxic, chemical lawn. I used to be more into grass/mowing in OH, but as hot as it is here, I just don't want to mow any more than necessary, no idea how to cultivate the grass here on purpose. And even right after mowing, it's not comfortable on bare feet, blah. We cut it as low as possible, as rarely as possible, and rejoice when drought or cold makes it stop for a while. I'm hope someone who appreciates fertilizing/cultivating grass will pop by with something actually helpful to answer your questions. Good luck!

I know that some people have grown Palmetto St. Augustine at least as far north as the Tulsa area and have been happy with it. However, there will be years where it may freeze back significantly. While it can tolerate more cold than 'Raleigh' St. Augustine, one thing that is really hard on all St. Augustine in Oklahoma is when we have a really mild spell of winter weather for a prolonged period so the grass doesn't even go completely dormant, and then the temperatures suddenly plunge extremely low in just a day or so. It is that abrupt change from a warm and mild winter to a suddenly bitter cold one that often hurts St. Augustine grass. I am as far south as you can go in zone 7b southcentral OK without crossing over into Texas, with Texas to my east, south and west and we have problems here in our county with early freezes or big fluctuations in winter temps causing a lot of St. Augustine dieback. It is my favorite grass. I had 'Raleigh' St. Augustine in Fort Worth in the 1980s and early 1990s and loved it, loved it, loved it. Our next-door neighbor here had St. Augustine when we moved here and I said I was going to watch his and replace our bermuda grass with St. Augustine if his grass thrived for a couple of years. So, here we are 14 years later and his St. Augustine is almost entirely gone, and we still have our bermuda grass. I wouldn't make a huge investment in it initially. Is there a sort of out-of-the-way spot in the backyard where you could plant a small area of 'Palmetto' as a test and see how it does for a couple of years before you commit to planting a lot of it? By the way, the people who posted about 'Palmetto' on this forum a couple of years ago had found a local source in NE OK but that was probably 3 to 5 years ago and I don't know if it still is available up there. Down here, I always see some St. Augustine plugs or sod in local home improvement stores like Home Depot or Lowe's, but probably not until late April or May. Dawn