to break a hole through hard pan in their gardens...
Hey Marv
Better to improve soil tilth than to use brute force here. Employment of brute force will need to be repeated after every soil compaction. Soil with poor texture shall become compacted after being uncompacted. Not the sort of thing desirable in growing most garden edibles. I go with about 4# of organic stuff/sq ft/year on well-developed garden soil. About 10#/sq ft in first year to ammend junk soil. The "Townie Gardening in Compacted Soil with Miracle Grow" approach is not my notion of "proper" gardening.

Reggie

My problem is more about drainage. My soil is pretty much 100% silt after you get down 12 inches. It does not drain well. I use a long fork or broad fork to break up the soil. This goes down about 11 inches. I am about 12% organic material.

We have used one in heavy clay soil and what I have found is that even though you made a large hole that you can then ammend, the soil on the walls of the hole are still compacted. If you are talking about using the auger to aerate all of the soil in a bed and then ammending the whole bed, that is a good idea --- lots easier than breaking your back (and digging fork).

Hey Marv,

Soil drainage and moisture retention are both beneficial components of good soil tilth. For example, soil "horizon" in my main patch consists (from top down) of about 5" of very loose stuff (horse and previous "soil") which refuses to compact regardless of traffic and precip. Very EZ to cultivate with scuffle hoe or other hand implements. Has excellent water-handing characteristics also. Further towards Hell (if your believe in such) resides increasingly heavier soils containing various clays in not insignificant representations. I do not attempt to deal with this horizon. Not needed for most cultivars (some root things, like mangel root and parsip root and carrot root) could benefit from a deeper loose strata.

Also, it is, IMO, a mistake that some Townie Gardeners make is to "over-till" the damn thing... rendering it to bug dust. May look pretty, but the size consist repeated tilling produces promotes faster soil compaction which is not desirable.

Reggie

Thanks Reggie. 2 years ago I dug down about 2 feet all over my garden and added tons of composted leaves. In some areas I might even have gotten down 3 feet. I could stick my hand in without any resistance. It was a lot of work which I will not be doing again any time soon. For the last two years I have just been piling on the compost and lightly tilling it in the top 6 inches. I am hoping I will be able to garden without tilling at all in a few more years for my tomatoes. I will just be making planting holes and the rest will take care of itself. I just thought it might help a little to drill a few holes around where I plant just to "maintain" it a bit.

I think you need to install a drainage system. Similar what they install by foundations.

With drilling holes, I think you should fill it with chunky gravel and small stones ( like a mini well) so the water can go down.

Here is the deal....working with hardpan (clay) soil is never fun. Regardless of how you amend...the dug-out portion of your native ground will act as a container/pot. The bigger the hole (pot) the better. My trees can break through the clay after they get somewhat established. I need the aggressive roots...that is why I do not buy semi-dwarf or dwarf trees. Most plants are just not tough enough to break through hardpan clay. Rocky soil is another matter. Some sections of my property are more "stratified" with clay than others. Wish we had sand instead....

I once read a book on edible landscaping. The author tried using an auger to make planting holes: he found that in clay soils, the action of the auger actually acted like a potter's wheel and slicked the walls of the hole. It compacted the clay and made it harder for roots to penetrate.

IIRC, he said that if you were to use an auger, you should also take a spading fork or some other instrument and break up the walls of the hole made by the auger.

I use a sub-soiler and run several times through the garden and out several feet. If I don't then the garden becomes a giant clay bathtub. If you don't have access to a tractor and sub-soiler doing the same thing with a shovel would work. I would put in some sock pipe so I wouldn't have to do it again though.

Another Catch: If your garden soil is well treated with compost , all kinds of organic matter to a depth of about 2 feet, then you should not worry about what is under that ; It could concrete or solid rock. Most garden veggies grow in the top 1 foot. If that is well drained, then that it all you and your plants need. That is how RAISED BED concept deals with it.

I guess the above idea would parallel growing in a two foot deep trash can with no drainage holes....not sure about that one. Who...what is a "sub-soiler"? Is that like a roto-tiller? Your concept makes total sense.

A subsoiler is a single blade that attaches to your 3 point hitch. It is a couple of inches wide. Most go down about 2 feet. To break up hardpan you will pull with your tractor. Will work gine if you can get all the way through the hardpan.

I've used a tractor with an auger and it works a treat! I planted over 40 trees that way. Alas I no longer have the auger..and have hardpan..I'm going to try a big drill and if that fails..get out the digging bar and get ready for some backbreaking work!! Soak hole dig ..soak hole dig..and repeat!

But you need to punch holes thru the hardpan so the tree can drain. I fill the hole with water and if it hasn't drained overnight..get the digging bar!

But as someone said if shallow rooted plants I won't go thru but with trees it is necessary!

I'm not sure what hard pan is, but I've used an auger (a hand-held post-hole-digger type) to drill through about 2 to 5 feet of clay, and I planted tomatoes in it. (How deep a particular hole was depended on the plant's length; I started them very early so I could plant them deep.) I probably won't be repeating that experiment, though. Tomatoes don't need to be super deep.

A hard pan occurs when a plough is used. The plough pulverises the top -- I don't know -- foot or so of soil to a too fine consistency, ruining its structure. Underneath this fine layer is the hard pan.

Ploughing is not healthy for the soil.

Hand digging with a garden fork or spade, however, is an entirely different thing. If you dig when the soil is damp but not wet, it won't damage things (apart from the odd worm who finds himself in the wrong place at the wrong time). Good exercise for the digger too.