Raised Beds on Poor Clay Soil

I decided to cut back my cover crops and start mulching.  The section on the right is mulched, the section in the middle is just chopped up, and the section on the left (also the background) is still in cover crops.  I had initially got Korean Lespedeza and Ryegrass to grow with heavy manual tilling, lime/gypsum, and limited compost/manure from a hardware store (only had to irrigate for a few days to get seeds established).

The raised beds are made with logs from clearing this area of trees.

Current challenges will be getting all these wood chips spread by hand and getting them broken down on a large scale (mushroom slurries maybe or some of the Fungi Perfecti kits).  N sources would be nice, just hard to come by in the suburbs (maybe I'll just have to rent a truck someday and pick up horse manure somewhere).  I think I will keep adding gypsum and lime for a few more seasons.

The soil is mechanically broken down to where I can almost broadfork downwards, but still has huge chunks of clay and grass roots.  Hoping to just keep on adding wood chips, heavy broadforking, and other amendments.

Sounds to me like you are on a good path, at this point though mulching will give better benefits to the soil.
If you can acquire horse, donkey, cow or sheep/goat manure to add to the soil, it would be very worth doing so.
Manures provide minerals, enzymes and other things that are great for soil building.
Manures are natures mineral replenishment and bacteria and fungi love manures, so much so that even after composting these critters will come back strong and inhabit all areas they can find.
Fungi are going to make serious improvements to your soil at this stage.

Redhawk

Thank you Dr R, I will be looking into the manure and fungal aspect.  Do you have any ideas for productive crops that would do well next year in fairly marginal soil (leaf crops perhaps)?

Josh Garbo wrote:Do you have any ideas for productive crops that would do well next year in fairly marginal soil (leaf crops perhaps)?

Don't sell yourself short on clay soil. Just because it is difficult to work (mud balls then baked like adobe in the heat) does not mean it is a poor soil. Clay traps nutrients and is a great soil. Daikin radishes and clover are good cover crops. You can also plant some winter wheat or even rye grass as a cover crop.

One thing you should not do:  Till those wood chips in. Clay retains moisture and if you till those wood chips in they will also retain moisture and it will never dry out. This promotes root rot and those chips do indeed rob plant roots of nitrogen. Rake back those chips and then plant/till if you need too.

I covered my 3K sq ft garden with wood chips for 6 years. It was a new spot so I did till for the first 6 years.  I would rake back all the remaining chips that didn't break down, till in the stuff that did break down (and added composted manure) then buried it all again in wood chips after planting. It took 6 years before I could go "no till". I still bury my garden in wood chips however I am no till now. It took that long to get my soil where it was "workable" by tilling in broke down wood chips and composted manure.

I'm south of Nashville btw and we have pretty much nothing but clay (red).

Josh Garbo wrote:Thank you Dr R, I will be looking into the manure and fungal aspect.  Do you have any ideas for productive crops that would do well next year in fairly marginal soil (leaf crops perhaps)?

I'd go for kale, mustard and collard greens, seven top turnip (for turnip greens) and you might try some of the broad leaf lettuces.
Beans will grow there as would watermelon, cantaloupe, winter squashes, peppers, even strawberries would most likely do well in such soil.

Once the plants are up to about 3 inches tall, start covering with the wood chips and keep adding as the plants grow. (DE sprinkled on each layer of chips will help a lot with keeping bug and slug traffic down)

If you happen across any mushrooms growing on logs or trees, taking some of them home to breakup and adding to the chips will do wonders for both breaking down the chips and introducing fungi to the soil below.
Compost will bring many of the other players in the microorganism world and they too will take up residence in that soil.

Redhawk

Experimenting this year with planting some vegetable crops directly in my unamended Adobe clay soil, I had very good success with squash, tomato, and cabbage.  I had poor results only in my tomato that was a thin layer of 1 yr aged eucalyptus mulch.  Everything else grew wonderfully that was under Oak mulch.

My strawberries and raspberries were planted this year into rows that were mulched in the fall with horse manure, and are doing wonderfully.

My year old swales which I filled with horse manure and wood chips has composted to a beautiful material, and the fruit trees in particular that had the horse manure amended swales uphill have put on impressive mass.

Keys for my expansive clay appear to be adequate moisture and a decent mulch layer.

hau Michael, It sounds like your tomatoes succumbed to the allopathy of eucalyptus. Those particular tree species have a very strong allopathic set of exudates, so much so that most of them grow in barren land (except for the eucalypts themselves).

A friend of mine has successfully composted eucalypts but he takes two full years, composting as many other plant materials with the eucalypts. He also adds mycelium to this heap, then he starts over, going through the whole process a second time but with no additional eucalypt materials for the second run.
He can then use the resulting compost as a mulch or even as a soil amendment, this year he started some seeds in the compost just to find out if they would sprout, and they did. He trialed tomato, yellow squash, carrots and cucumber seeds, the sprout rate was around 89% which is good for any seeds.

Redhawk

Yes, powerful stuff.  I thought after sitting for a year it would be mitigated but it's clearly still quite detrimental.
Your friends composting method sounds like a good option.  I'm just glad I didnt use it even more broadly.

its been 4 years, just wondering how your clay soil is doing now? I saw this and was thinking of a patch of this poor red clay soil on my place where I cut and split firewood for the past couple years. I tried to plant a tree in this area when I first moved here and it didnt survive. and after moving from florida where every place you put a shovel in the ground out comes sand and coral rock. this was rich red clay, could be put right on a potters wheel and produce kitchen ware. I was noticing yesterday how the area has been transformed. just scratching g at the sawdust and wood chips reveals an abundance of earthworms and everything wants to grow. new trees sprouted and want to take the area over. full disclosure there are boxwood and black walnut trees sprouting vigorously all by them selves and several types of aggressive vines that pop up everywhere.
but the area with all this saw dust, wood chips and old bark is truly transformed into something completely different after just 2.5 years