Very nice. Innovative, too.

Off-topic, but important: that black pipe is going to heat up in the sun and cook your poly. Make it white. Use latex paint only if you paint. White duct tape works, too. Also, the treated lumber is going to slowly ooze out its chemical treatment and dissolve the clear end panels. But it will take a while.

I have a clay soil in Illinois, and people here tend to use gypsum as an amendment. I really like greensand. It is supposed to break up clay and work as a nutrient catalyst. Beyond that, you would work in organic matter, like compost or composted manure of some sort.

The structure looks great - nice work! Bonus points for re-using oilfield piping too.

I think any of your proposed plans for soil prep will work. Taking soil out will work, but it's going to be a lot of soil. Where will you put it? Building boxes or mini raised beds would also be lovely but that's also going to require quite a lot of materials. But you'll have a beautifully organized space if you go that route.

Our GH is similar in terms of soil. After the GH was built the only soil remaining was a clayey, alkaline subsoil that tends to form concrete-like balls. So I took some of that soil out, then added peat moss, composted manure and gypsum. I also added a frame to create a slightly raised bed. Over the first few years the clay balls kept coming to the surface so I took them out and continued to add gypsum and other supplements. Now (year 4) we're there. The soil seems happy and I don't need to add any more amendments for the time being. I still add a low nutrient, balanced organic fertilizer any time I plant anything.

I too grow something in the beds year round. I rotate things around but there are still some prime spots that always are very busy. Our extension office person said that would be OK so long as I kept using low level fertilizers and aiming to keep organic matter in the 10% range. So far, so good!

Good luck - let us know which route you choose.

Thanks for the excellent advice about the black oil field pipe, Cole. I had not thought about that. My GH will be cooled by the two large evaporative wall cooler panels at the back (you can see them in the picture), but I can see how the black pipe will heat up in the sun. I will most definitely paint it white. Great catch!

Thanks you Karin for your personal experience. How high do you think I should build my raise beds; 4 inches, 6 inches, 8 inches or other?

Hmm, the height is up to you depending on how much you want to spend on materials. Ours is just 4." Making it taller would allow for better drainage and would give you more room to build new soil. Of course, you would also have a bigger task there because you'll have to fill the beds.

Another important consideration is that the taller bed will get colder in winter as it is not as well insulated by the ground all around it. If you are interested in maximizing your winter growth but not heating things too much, then I suspect that lower is better.

Whew! That's a relief. I was worried about how much material it was going to take to fill up the beds if they needed to be taller. Thanks.

Now to the actual composition of the material to put in the beds. What would be a good all around mix for the widest variety of vegetables?

Well, what do you have available? Is there a place that sells lovely black soil? Or organic compost you can mix into your existing soil? Buying compost is tricky - it's hard to find one that is genuinely free of bad stuff. Many contain "biosolids" (human waste) or manure from animals that are fed who knows what. Local farms are a good source of manure so that is one place to check. Your extension service might also have suggestions on what supplements to add to your native soil to make it good for intensive growing.

If you are only going up 4" then you can probably take the route of adding amendments to your existing soil and working it up into something nice. I have had good luck with the combination of peat moss, composted goat manure, sand and gypsum.

I have a large chicken flock so what I personally have available is chicken manure. I have heard that you can buy tree mulch from the city for 20 dollars a pickup load but I think it comes from the trees the trim around the power lines, so it will be made up of many different types of trees. I have a friend who can get cotton hulls and that is supposed to be good to mix in with the soil. Before this drought started last year there was a guy who said I could have is much cow manure as I could shovel out of his corral but 70 percent of all cattle in texas were sold last year and I don't know if he still has any.
any.

Nice to have a handy supply of chicken manure - I would start with that, plus peat moss or gypsum and whathaveyou and see what you get. I figure that building a good soil is an iterative process and it will take a few seasons to get things to where you want them. But you will be able to tell how it's coming along and what's needed and you can go from there. A soil test is a good idea somewhere along the line.

Wow 70% of all cattle in Texas - that is quite a sobering number.

I have heard that it is best to compost chicken manure first because it is very hot. I was thinking of getting a soil test done to start off with and that should tell me what I have and what I need to add. Never had a soil test done before. Where do you get that sort of thing done at?

You might try your local county ag extension center or your nearest state university and see if they offer free soil testing. If you can't find the service offered for free, here is a company that will do it for $40 for their basic test:

http://www.texasplantandsoillab.com/soil-test-kits.asp

That's just one private company I found. I'm sure there are others.

Yes, I have also heard that chicken manure is high in nitrogen when it is fresh. But if you compost it a bit and mix it into you native soil, it seems to me you would temper that a bit.