Nothing like Gulf Coast gumbo clays to challenge a gardener. There are a number of approaches, but which to follow depends a good bit on what you want to plant and grow.

First - forget about digging out and filling in with a more desirable soil. That will leave you what many refer to as a bathtub. Basically you will have a clay tub filled with nice soil. The when you irrigate or get substantial rainfall, the tub will fill with water. It's not a good scenario for long-term plantings.

For permanent installations it is generally best to plant species well suited to the native soils, and there are many. Just look around and they will become evident. A second choice is raised beds. But most perennials will still want to root and grow at depths beyond the common raised bed depth. So again, plants well suited to the native sois are your best bet.

You can improve your heavy clay soils by incorporating a fair amount of organic matter (compost, etc.), up to 10% by volume in the first 6" of soil. Then follow with a 4" layer of a wood-based mulch on top after planting. Add new mulch periodically to keep at least a 2" layer on top. Over time the clay soil beneath will become better.

For annual plantings of flowers, veggies, etc., raised beds with more highly amended soils or imported "garden soils" work well. The key here is enough depth, and to build them on top of the natural grade. That way you end up with a false bottom tub, and the water not only drains through the bed soil, but away as it hits the clay beneath.

For annual plantings TAMU recommends the addition of 3" of expanded shale tilled into the top 6" of soil (produces a 3" raised bed), then followed with 3" of compost tilled in on top of that the new 6" depth for a 6" raised bed (see link below).

Here is a link that might be useful: Expanded Shale - A new Possibility for Amending Clay Soils

Don't know why I didn't notice this before. I totally agree with the above, just keep putting OM on the surface when it presents itself. Leaves, lawn mower bag, small yard trimmings, kitchen waste buried slightly so it doesn't harbor fruit flies, mulch, pine needles, home made compost, anything you can get/find. The drainage will improve, as well as water retention in dry times. Similar to reclaiming an area from grass/weeds via smothering/lasagna.

This works in clay (in housing developments where I lived in OH, they take all of the top soil away to sell, then build the neighborhood,) and in sandy, won't-hold-moisture "soil" that I have here. I've never had any issues with bath-tubbing this way (but have created such situations amending holes for larger, woody individuals installed mid-lawn,) in a bed because the surface and below isn't disturbed, which through experience I know is unnecessary if one is patient in not expecting instant results. The forest floor is a beautiful rich loam, with lots of humus and tilth, from layer after layer of decomposing OM landing on its' surface. The worms and other decomposing entities will, along with rain, distribute the by-products to their proper levels in the soil, as well as your digging here'n'there occasionally to add/move plants.

After just a few months of being covered with decomposing OM, a difference will be apparent. After a year, digging will be noticeably easier, the color different. After 2 years, there should be little trouble with drought or flood, depending on the surrounding topography and weather. Compared to areas that were tilled to start, I can't tell a difference when I 'dig in' after 2 years. It's one of the most addictive parts of gardening, to me, improving the soil, then observing those improvements.

Just remember that no 2 gardeners do everything the exact same way although both may have great plants. Gardening usually goes more right than wrong, and you have to pick the ideas and methods that work for you, your schedule, budget, climate, what's actually available for free or sale at stores, and just sounds like something you can do. Some of the stuff I read sounds like it would work great, but I just don't want to do it, or can't envision how it would benefit. I've learned that if I approach something about gardening with confidence, it usually works. If I'm hesitant and doubtful, haven't asked for enough opinions usually, it usually doesn't go well. My Mom and I have usually opposite opinions about any garden-related issue or topic, and her yard looks fine, so does mine, each according to their own taste. I wouldn't want her yard and she wouldn't want mine.

Going back to individual plants, Lantana could care less about any of this soil improvement, whether you do anything or not, so a good one to start with. Buddleia seems happy anywhere I stick a piece, sometimes in the middle of grass. Cannas are easy, but give them a spot you mow around,...

Just saw that you kind of asked the same thing twice. Hope one version of what I said is helpful/applicable in some way. Yes, I really do like to yak about dirt...

Moving to South Tx. from Pennsylvania has presented quite a challenge in gardening. I'm used to the regular soft soil, now all I have is several ft of this rock hard clay. I have done a little research & it says to try & ammend the soil by adding compost, & hummus. I did that with some top soil & 2 " of Mulch. So far I have only planted some Hostas, & Japonicas & a Split leaf phillodendrun. This is only late February and the weather hasn't quite settled yet. Keep you guys posted how I made out.

Well, I love to yak about dirt too, purpleinopp. I love turning crappy dirt into beautiful crumbled fluffy chocolate cake.

I live in St. Tammany and I have poor soil. My test showed low in EVERY nutrient, with very acid reaction 4.7PH and low low organic matter 1.7%. However, I have been able to substantially improve certain areas over time. I recently watched a video on the internet called "Back to Eden" (you can search on youtube and watch it for free) where a gardener in the Pacific Northwest advocates transforming the soil without tilling by layering organic matter over the soil year after year. He specifically uses ground up tree trimmings (like from electric company line trimmings) followed up with manure (he has chickens - but also horse manure is mentioned in the film). Every year he adds a new layer and the dirt in his yard was amazing.

I used to dig out all of my clay and replace with new soil. This worked OK if you created a large bed, but it was very expensive and back-breaking. So I converted to a sort of no-till. I got a huge load of tree trimmings thanks to the electric company last year and covered all of my beds with this material thickly. I notice after several months there are worms EVERYWHERE where I laid the trimmings and the soil is much softer and darker. It takes a long time but if you can get tree trimmings or find a source of horse manure, get a huge load in Spring and Fall and spread a 2-3 inch or more layer in all of your beds and faster than you think that clay will start to change into beautiful dirt.

In 2-3 seasons you should have some nice stuff, and if you keep it up after 5-7 years you will have amazing dirt. We are so hot and rainy here that organic matter breaks down exceedingly fast and must be replaced to keep the soil productive. So just keep layering that organic matter.

Plantlady, hope all is going well!

Jockewing, well said! The video you mention is here. I plan to watch it sometime in the next few days. If you haven't already, I encourage you or anyone else reading this to investigate the term permaculture. I also have an excellent book about this, Redesigning the American Lawn: A Search for Environmental Harmony by F. Herbert Bormann, Diana Balmori, Gordon T. Geballe. I've had it for a while but hopefully it's still out there to buy, or at your library.

This is one of my fav pieces of info (a short lecture) about 'dirt.'

We just finished moving and the first order of business was to extract the keeper plants. How easy and pleasant that was to do!! The bed areas were all full of soft, very dark, but not muddy 'dirt.' I'm not a big person and usually have to jump on a shovel a couple times to get it sunk in the ground all of the way, but a gentle push with my toes was all that was needed in any area reclaimed from grass a year ago or longer.

Until he died when I was 18, my maternal grandfather always had a HUGE garden, over an acre. He tilled it every year and I spent many many hours working in it, planting, weeding, harvesting. The ground was always hard as a rock when dry, muddy when wet, and although it was in Pickaway county OH (famously 'good dirt,') it never improved in tilth, stopped puddling up with water from poor drainage, or darkened in color, quite the opposite. Same thing with a friend's mom's garden that I visited and help with many times.

I couldn't be more convinced that following nature's plan of not disturbing soil unnecessarily (one has to dig a hole to add a plant,) and adding OM to the surface often or at least annually with a cover of leaves, is the best and easiest way to have a great garden. Tilling huge areas annually is what allowed the 'dust bowl' of the '30's to happen.

Also interesting was the very dark, spongy rectangle of soil under the shed part of our carport. When it was disassembled to move, I was amazed to find such conditions. We had laid cardboard on the ground that had plastic on one side, then some wood pallets to keep stored items from getting wet. There was nothing left of the cardboard but the pallets weren't rotting at all, so not part of the OM contribution. This made me think even a small amount of OM can do wonderful things, and that the huge amounts, by comparison, that I put on beds are no doubt causing wonderful transformations.

If it ever stops raining, can't wait to get started from scratch again here at our new place.

comfrey and dandelion have long deep roots
that break up the soil.

Personally, i dig as deep as possible and add a lot of coffee grounds.
i get them at starbucks. sometimes 10-20lb 2-3 times a week.

the best way ( i found) for use coffee grounds is to lay them out on a tarp in the sun 2-3 days.
this breaks them down faster than composting.
then, you can either add to a compost bin, or mix in with the local soil.
When i do this, i add builders sand (very coarse) + compost and/or UCG...
i mix it up well, and add enough UCG and sand so i am a few inches above grade.

Some people told me it wouldn't work,
but its worked great for me.

Its possible my area is different than yours.
part of my yard is clay, other parts are river sand.
perhaps this changes the bathtub scenario...

Here is a link that might be useful: hugelkultur

also check out hugelkultur

this may be your best way out...

Here is a link that might be useful: hugelkultur