plant natives

You can top dress with compost, just a light amount (1/4 to 1/2 inch) a couple times a year. That will encourage earthworms who help naturally till the soil. I can tell you that growing SA on clay is preferable to sand, which I have. It's hard to keep it watered enough in sandy soil and the clay tends to drain slower. I suppose that fungus might be a bigger issue for you too, so be careful not to over water. All of the sod that I've seen for sale was grown in black clay.

Congratulations on the new house!

I would rent an aerator and run it over the lawn several times before adding the compost. A good aerator will remove small plugs of the soil, there by allowing the compost to settle in a little deeper. Down here I can rent one for about $60 for 24 hours.
Jim

That's a great idea, Jim!

Jim, aeration is a great idea. I used to have guys that would bring their core aeration machine and do my yard front and back. At that time it cost less than renting a machine.

However, the St. Augustine lawn might do fine as it is. I've noticed as the poster above did that St. Augustine bought as sod is grown on heavy black clay.

If your yard is sunny you might look into plugging a few pieces of the more drought and sun tolerant Floratam St. Augustine into what is there. We did that last year and the very vigorous Floratam has pretty much taken over the mixture of St. Augustine and Burmuda grass that we had. It's possible the builder used Floratam, but since it is a tad more expensive they may not have. To be sure you could take a sample to a nursery that sells both. Floratam has larger blades and slight bit different color.

Also I've found that fertilizing in the spring with soy bean meal and alfalfa pellets is FAR superior to using chemical fertilizer. This feeds the earth worms and microbes that feed the lawn, but you probably know all that already :-) Anyway, for the past two years I've been putting a 50 lb bag of each on my lawn and it's never been better.

Wishing you the best with gardening in your new home :-)

Here is a link that might be useful: Aerate lawn service Austin, Texas

I should of done the search for Waco! For some reason my mind registered Austin instead of Waco.

Thank you all for your feedback!

I purchased a coring aerator last week (the manual labor type) and am planning on going over the front and back over the next few days. Also I'm glad to hear that several of you recommend top-dressing with organic compost, compost is relatively inexpensive and I know that it gives all sorts of sustenance to the micro-organisms inhabiting the soil.

Have any of you tried adding gypsum after aerating? My mother suggested this, but the nursery I frequent couldn't really give me a definitive answer on whether or not this would be beneficial or not.

Gypsum is calcium based. Isn't Waco soil already full of calcium? If so it won't help. Gypsum is usually used on sodic soils(high salt and low calcium). Just keep adding compost a bit at a time until you're too old to care.

Oh and don't amended the soil when you plant a tree. Compost around it when you're done. Otherwise you'll run the risk of creating a bathtub that collects water and a tree that settles too low.

Many years ago I moved into a new house and soon thereafter bought and planted my first tree. It was a Magnolia and the soil was clay. I naively planted the root ball a little low.......and within a short time the leaves all turned brown and just hung on. Strike one. I dug up the rotten roots, bought Magnolia tree #2, and planted it in the same place and at the same low elevation. Strike two.I later learned that experienced, successful planters would have planted those Magnolias in a raised mound of sandy, organic soil formed on top of the clay. The Magnolia's roots can develop above and eventually grow downward into the moist clay when ready. Plant drownings caused by me are at an all time low because bunches of trees have since been planted higher than the clay in formed mounds of good draining, sandy, organic soil mix. A few years ago a new neighbor in his new house nearby bought a new Magnolia tree and planted it in his new front yard. I stopped by, did the "intro/welcome here", and then asked him about why he planted his Magnolia inside of a clay soup bowl like I had twice done. He later told me that he pulled it out and replanted it higher. The roots were soggy/sloppy wet when he pulled the tree out. This tree is really beautiful and healthy after several years of growing in it's new mound above the clay.

That is great advice "coping" and when I planted the magnolia, I mixed in organic soil and compost with the clay (which I broke up as much as possible before using as backfill). I've also built a berm around the trunk, and I've left the top of the rootball slightly exposed and a little higher than flush with the ground around it. The tree does seem to be doing better, perhaps just experiencing a little shock from being transplanted, but I will continue to monitor, and if need be, I will replant it a little higher. Thanks for the advice!

The 2 that I drowned also had a berm around them that I thought would beneficially retain water.Good for planting in fast draining soil where water runs off.....not for preventing excess water from escaping.....When you dug into the clay, was it very dense and packed from not ever being disturbed? The tiny clay particles in undisturbed land swell when water-logged and hold the water well, which is why ranchers wanting to have a pond/water tank formed in their sandy land will have clay hauled in and a dozer will spread about a one foot thick layer of clay over the dug out area so the water will stay put and not drain away. When you insert the much-less-dense root ball and compost into the hole, well..., it is about like putting a sponge into a glass cup. As you pour water into the cup, the sponge will soak it up and stay sloppy wet....and excess water will not drain down/away through the glass. Okay for hydroponic gardening......but not for Magnolias, etc., etc.

You've gotten lots of good advice, so the only thing I will add is to mow the grass as high as your mower will allow and mulch mow.

Carla in Rowlett, TX

In clay soil if you amend the soil be sure you cut a drain path for the water to run off or as shebear says it will create a pond to drown your trees. You can also drill some good size holes around the drip lines and place PVC with lots of holes all up and down the lengths and place gravel to fill them up making sure the PVC is a little below the ground level for deep root feedings.

My parents live on the blackland clay in Dallas County. The only thing they ever did to their St Augustine lawn was water it deeply and plenty, let parts of it grow about 6 to 8 inches high all summer when they wanted that part to cover an area quickly, and fertilize it with grass fertilizer once or twice a year. The lawn has lasted more than 40 years.

Thanks to everyone who has helped to reassure me that the clay which is so tough and sticky on gardening tools is not the kiss of death for plants! I will be manually pulling plugs of sod this week to aerate and will be top-dressing with compost in the coming weeks, but I will turn my focus to raising a healthy, organic lawn and flower beds rather than altering the natural soil beneath.

clay soils most likely do NOT have enough calcium, that is why they stick together like that. Gypsum will improve the structure greatly. I did this when I bought a new house, found the clay almost impossible to work without machinery. I spread gypsum pellets by hand, watered it in. By the next day, I was able to dig almost 12" deep in beautiful soil (by beautiful, i mean the texture was crumbly). There were areas that needed additional gypsum, but I could save that chore for another year. I was happy with the single application. Also, my plants grew really well whereas before it seemed I would have deficiency issues when planting in clay.