Put in drain lines and forget about the amendments. Or buy sandier soil and dump it on top, plant in that (without mixing it in).

I had a great article years ago that I can no longer find, written by an OSU (Oregon, not Ohio) prof whose name I've forgotten :) Organized, I'm not.

But his recommendation for clay was to spade in 3 - 4 inches of coarse compost, followed by spading in 2" sharp grit or contractors sand. Compost first in order always, or the sand addition can make brick. Top dress with more compost annually over the years, keep those worms working.

I've always used that method in my own beds, and the clay based soil is becoming remarkably easier to work with - not an overnight fix but definitely better over time.

Compost decomposes and returns you to original soil if not replaced periodically. Sand content has to be more than 60 percent before soil starts becoming sandy. How loose do you need it, how many tons of sand do you want to buy, spread and dig in? I'd rather but the money and effort into spreading and raking out a suitable soil that is ready to go, skip the forking in.

I've put just organic matter in compact clay soil, and with cultivating, could shove a blunt bamboo pole over 12" into it in the spring without loosening it after a whole winter of rain.

At one country club I worked at, the superintendant - with an agronomy degree - agreed that the sand applied on fairways only firmed the surface, but ruined the drainage. Drain lines and catch basins were needed. It was just a hardtop to get carts across.

I've written a piece on it at this website page - ending with two related topic links.

Here is a link that might be useful: Landscaper / Ex-Greenskeepers writing about soil / sand

You can spread wood chips over compacted subsoil and have it loosen up as well, without cultivation. It's the moisture that softens it, mulches shade soil from the baking effect of the sun and enable it to remoisten.

I agree that wood chips may fit the bill in some applications. When we lived north in Beaverton, Oregon, I had several tree companies delivering chips to the wooded area below the acre we landscaped.

It decomposed very nicely after a year or two.

Organic matter like that - or bark - releases a complex sugars; polysaccharides, that can leach down and cause soil to aggregate to a degree.

Moisture softens soil for pliability, but also provides lubrication which can enable added compaction - even from rain drops.

So the chip cover can prevent compaction.

There is a substance that's worth looking up on the internet.

Glomalin

I think that's the correct spelling. You will have no problem finding top notch information with a Google search.

It was found quite a few years ago, but thought to be some kind of waste or residue. But in the mid-1990s, research found out how it's produced and how it improves soil condition.

Pioneer species like moss on rocks or alders on Alderwood till build up organic A horizon with their litter over time which enables other species to grow. To see how it works you just have to dig around in a wood or even an old garden. In climax tropical rainforest with thousands of species per acre, including towering trees there is hardly any topsoil due to rapid decomposition in warm and nearly saturated atsmosphere. But there is usually a litter layer.

In nature bulk organic material ordinarily encounters the soil at the soil surface, not well below it.

Here is a link that might be useful: Myth of Soil Amendments, Part II

Put large loads of the best organic compost on top and plant in that. Keep in mind that clay has the most nutrients per square inch, but is so dense that it is difficult for roots to access them. The other method is to til in the compost.

I learned in a soils class that adding sand to clay will just make it into the texture of cement.

AMENDED CLAY SOILS ARE VERY FERTILE -- AFTER SEVERAL YEARS OF 3-4" OF COMPOST BEING APPLIED & MIXED IN, OF COARSE
1)GET A SOILS TEST DONE TO SEE WHAT NUTRIENTS ARE NEEDED & WHAT IS NOT HELPFUL -- 1ST YEAR PROBABLY ROTOTILL ~ 8-10" DEEP TO THOROUGHLY MIX IN THE AMENDMENTS...
2)LAY OUT GARDEN BEDS & ONLY STEP ON THE PATHS-- PACKED CLAY = HARDPAN ADOBE & USEFUL FOR BRICKMAKING, NOT GARDENING...
3)USE SOME FORM OF RAISED BEDS FOR GOOD DRAINAGE FOR ROOTS...
4)ROTATE CROPS & AIM FOR YEARLY IMPROVEMENTS... BY THE TIME, A 3 OR 4 YR ROTATION SCHEME COMES BACK TO THE ORIGINAL VEGGIE FAMILY, YOU WILL PROBABLY NOTICE MUCH IMPROVEMENT, EG TOMATOES NEED TO BE 30" ON CENTER, INSTEAD OF 18"... FEWER PLANTS BUT MORE PRODUCTIVE...
5)PLANT WINTER COVER CROPS, OR SEVERAL INCHES OF LEAVES HELD DOWN BY CARDBOARD & WEIGHTS, SO THE WINTER MONSOONS WON'T POUND YOUR CLAY INTO HARDPAN, EITHER...
GOOD LUCK & GOOD GROWING TO YOU,K

Debb, I had the same problem when I moved into my new home.

There was absolutely no top soil - just glacial till. I was stymied as to where to start because I would have to haul in so much topsoil to have any type of plant.

I did rototill the first year and of course brought up zillions of weed seeds.

I brought in probably 20 yards of compost, aged sawdust, mulch, and tagro(treated sewage available in Tacoma) and spread it in my small backyard and front yard over the course of the next two years.

I took bags of leaves and grass clippings from the curb on recycling days. I also asked for the bales of hay from store displays after Halloween.

I got huge bags of coffee grounds from Starbucks.

My soil is now well-drained and full of worms. There were no worms at all when I started.

The only time I lose plants now is when I neglect to water in the summer.

Oh, and the clay is still there, under the topsoil, penetrable only by pickax. Susan

Clay soil is a problem for me too. I have put bark mulch on flower beds and it certainly improves the consistency of the soil as the mulch breaks down. I have a large veggie garden area that is losing ground as the soil packs down (I haven't added any amendments for a few years) and I am thinking of getting a tree trimming company to deliver a truckload of chipped branches which I will spread on the pathways and use in fallow areas. I think this will keep the weeds down and by next year, it might be ready to be tilled in. This year, I will add manures and composts just to the planting areas -- I intend to keep them small and work on improving the overall soil in the garden. Do you think this will help?

I cannot imagine how sand can turn soil into concrete. Any amount of sand will tend to keep clay particles from adhering to each other, thereby improving drainage and aeration. I think the problem is that people apply a sprinkling of sand and expect miracles. By definition, a sandy loam soil (a very desireable soil type) contains over 50% sand by volume (Foth, Fundamentals of Soil Science, page 29). So if you want to turn a 6" depth of clay into sandy loam, you will have to mix in 6" of sand. That's a LOT of sand, but you can buy sand for around $200 for 10 cubic yards. Sand with gravel up to 1/4" is fine. For large areas, you really should consider using a tractor with a bucket and rear-mounted tiller for this job. Organic matter is also very beneficial when added to clay soil, but its effect is temporary. The sand is permanent. When I amended my heavy loam soil, I added several inches of sand and about one inch of compost, and dug it in 12" deep.

If you have nothing but nasty subsoil clay, then I agree with bboy that you should buy some good soil and put in on top of the clay. You can rake it out and start planting on the same day, as opposed to years of back-breaking work trying to amend your clay.

You need to distinguish between a poorly textured soil with bad aeration and drainage, and a high water table. If you dig a hole and it fills up with water, you have a high water table, and no amount of soil amendments is going to fix that. As bboy suggested, install a drainage system. But be careful. Designing the right drainage system is a job for an expert. If you screw up, you could end up with no improvement, or you could end up with a clogged system after a couple of years, or you could get sued by your neighbor for flooding his property.

On the other hand, if your water table is fine, but your soil texture is lousy, a drainage system isn't going to do a thing for you except drain your bank account.