Tiller vs. pitch fork

[Northernfox]

I have to cut in wood mulch/ compost. Do I need an tiller or will w pitch fork work

[rainbowgardener]

I would tend to use a shovel not a fork. Tines aren't real good for lifting and turning under. Whether you need a tiller or a shovel depends on how much area you are talking about. I have 200 or so sq ft of veggie beds, which I only turn manually. If I had an acre, it would be impossible and I would either have to get a tiller or learn how to be totally no-till.

I prefer turning under with a shovel (or even a trowel! ) because I think it is less destructive to the soil life than running a tiller through. But I am doing less and less even shovel turning.

[applestar]

Just to be clear --

You don't want to bury the wood mulch by evenly distributing/tilling. You want to leave wood mulch on the top surface of the soil as mulch.

Garden fork is for digging rather than pitch fork. "Garden fork" has 4 sturdy pointed, flat/squared tines that are usually triangular in shape for greater strength, and are meant for digging. "Pitchfork" has 3-4 slender long, round tines for tossing straw and hay. There is also "Manure fork" which has closely spaced metal or plastic tines for scooping out/up manure.

...there is another name for "garden fork" that I can't think of .... Spade fork?

When I'm thoroughly digging in compost, I tend to double dig which when done correctly is supposed to not disturb the upper soil structure/layers too much. For this purpose, I use the flat/rectangular spade to dig the trenchs and pick up the clumps of soil. I use the garden fork which has the same width as the shovel to dig the compost into the bottom. For most other garden work, I use the pointed curved shovel (which to me is the one that should be called spade because of the shape but for some reason they're not....)

OT -- I have a 4-tined pitchfork that I use for turning my compost pile. Garden fork's flat/triangular tines pick up the moist large pieces/early stages compost ingredients in a clump then won't let go so I have to scrape off each time, but pitchfork's round tines let's most pieces slide off if stabbed (dry leaves can be an exception). When the compost is neary finished, the pitchfork allows smaller pieces and particles to fall through and let's me pick up the less finished pieces to turn. I'm thinking a closely tined manure fork would let me sift through finished compost to remove the biggest remaining chunks without having to run the whole pile through a wire screen -- that's on my Wishlist.

[gixxerific]

To go further on the topic of turning under wood chips. Big chunks of wood when turned in can create a lockup in nitrogen. A lot of energy will used to break down the wood which is a good thing in the long run. But in the short run it cause as I said a N lockup.

I would not mix that in if were me. Leaving it on top will allow it breakdown without causing havoc underground.

I am getting away from tilling. Though I got the tiller out yesterday. It is much faster than a fork. I just mix up the first few inches very quickly. Going down to the clay subsoil I have can create a hardpan which is hard for roots to penetrate, though they will, have you ever seen a tree uproot a section of sidewalk. Roots will go where they want and you can't stop them. Some say that a fork or double digging is better than a tiller since is does not mess up the biological army in the soil. I say that is bull they both disrupt the soil biology.

It's like the difference of hunting with a gun or an bow and arrow. They both the same job just in different way's

[joed2323]

gixxerific- I'm curious to why you say you are getting away from tilling?

I think tilling is the greatest thing since sliced bread, especially when you are opening up say a addition or another smaller garden in your yard elsewhere.

[digitS']

I can't answer for Gixxerific but I will say that tilling in grass roots isn't always the best way to kill the grass to prepare for garden plants. You may have to till again and again and again. allowing the grass to grow back in between tillings. For warm-season plants, there may be enough time to kill everything that was growing on the ground previously.

I use a spading fork for much of my garden work. If I am on new ground, they are a good choice for loosening the soil around grass and weeds so that they can just be pulled by hand or flipped out of the soil with a 4-prong cultivator.

If I am trying to incorporate a moderate amount of compost into the soil, I may just use the tiller attachment on the weed whacker. That keeps me off that piece of ground with my big feet and 200# of weight. I've got 2 sizes of tillers up from the weed whacker. I would prefer that both of them stay in the garage . . .

Steve

[joed2323]

I may of been unclear before, yes I agree especially if the grass is rock hard, the tiller likes to bounce all over the place, I would rather cut most of the grass out with a shovel to try and get most of the grassy/weeds out of the top layer, I try and skim the top of the grass off and leave most of the good dirt below it, then run my tiller through a new area.

This may not be the best way to do things but it works well for me, especially in the early spring after all the frost comes out of the ground, the grass digs off fairly easy...

Some grass may grow back, but thats part of pulling weeds in the garden, some people hate pulling weeds, but I can come home from a hard stressful day at work and go out in the garden and pull weeds, it somehow relaxes me. I stay on top of weeding, the smaller the easier they pull out...

[Northernfox]

Thanks!!

So I am bringing in wood/compost mix to help with a severe density issue in my garden soil. I believe the issue is the soil was pulverized and run through a screen as a part of my neighborhoods construction.

So the small wood chips and compost should help with the compaction that happens over the growing season allowing my plants to use the soil much easier.

I will be using my garden fork as I don't have a pitch fork . I guess growing up above the arctic circle did not help with my garden tool know how. I also have both a flat spade and pointed shovel.

How deed should I mix and what would be a good ratio?

I will have strawberries onions peppers and carrots between the three beds.

[Northernfox]

Some grass may grow back, but thats part of pulling weeds in the garden, some people hate pulling weeds, but I can come home from a hard stressful day at work and go out in the garden and pull weeds, it somehow relaxes me. I stay on top of weeding, the smaller the easier they pull out...

Oddly enough I find the same thing relaxes me that and eating the harvest

[gixxerific]

Joed why get away from tilling? It as well as any other disturbance be it rain, wind, temp, nutrients, water etc. can disrupt the teeming life that is within the soil.

Too busy to really reply. Come on over we can talk soil all day.

[imafan26]

I do agree that wood chips may not be the best solution if you want to do any planting right away. Compost is a good choice though, use more of it.

If you want to do less work, just use the garden fork to poke holes in the ground and build up from there with compost, soil, (maybe manure), and maybe some gypsum( if the soil is sodic and alkaline), to help with the drainage. Plant on top with deep rooted plants. They will help break up the soil for you over time. I have used pigeon peas, and sunflowers to do that. Use the wood chips as mulch only. Adding wood chips to the soil will require that you add more nitrogen.

Inoculate the pigeon peas if you can. They are nitrogen fixers, they attract beneficial insects and are edible. I don't know how hardy they would be in your area, but you can plant them as an annual. In the tropics it is a perennial.

Then there are raised beds and lasagna gardens that would be a whole lot less work.

[Northernfox]

All of my beds are raised beds

I thought pumpkins were aggressive rooters and they still got choked last year.

I might try using the wood chips in my compost. A few handfuls to help all the nitrogen source material balance out.

[imafan26]

It is strange that the soil would be so hard in a raised bed if you have been adding organic matter regularly.

OOPS! Clay! The organic matter holds water and so does clay. I have the same problem. It makes the soil mucky, heavy,dense and very hard to work with. On top of that as the organic matter breaks down, it compacts. I also have drainage issues at one garden that makes it worse.

I did have sort of a solution that worked better. I added cinders to the soil to improve aeration. It was a lot cheaper than adding perlite. I also had to back off on the watering. The top looked like it was dry but it was still wet a couple of inches down. Mulching the top helped that out.

I tried adding bark chips. It actually made things worse holding on to water and stealing nitrogen from the soil (I added a lot).

[Northernfox]

That is probably my issue. We have lots of clay!! Tell me more about the cinder? Was it the stuff from the bricks?

[TheWaterbug]

To go further on the topic of turning under wood chips. Big chunks of wood when turned in can create a lockup in nitrogen. A lot of energy will used to break down the wood which is a good thing in the long run. But in the short run it cause as I said a N lockup.

To follow up on this, at what point do the wood chips (or other mulch material) start releasing their nitrogen? Can you tell by color, texture, or smell?

I think I erred a few times by tilling in my free municipal mulch, thinking that it was going to be of benefit, and not remembering that it needs to break down further before it goes in the ground.

[Dillbert]

about a year.

[Northernfox]

Will it go faster if it is combine with your household compost ?

[Dillbert]

"fresh" wood chips / mulch will tie up nitrogen over a period of a year or so.

not everyone believes this; especially those using composted wood chips.

in the absolutely ideal conditions of proper carbon to nitrogen ratios, regular turned and mixed to ensure oxygen supply to all parts of the pile, proper moisture . . .

you can make "perfect" (whatever that is) compost in 60-70 days.

now,,, "perfect" okay. that does _not_ mean you will have no chunks of uncomposted unrotted unbroken-down wood.

there are gardening mystics that will sell you magic powders to inoculate / speed up "make more perfect compost even more faster"

Mother Nature does not have an open account with these mystics and for some odd reason has managed for the last several billion years. you're free to formulate your own opinion.

will it go faster? yes, no and maybe. depends on how expertly / actively you "manage" your compost heap.

[TZ -OH6]

I'm going to say some unpopular things here so if you are an organic warrior stop reading now please.

Wood chips have a nitrogen to carbon ratio of something like 1:100 to 1:400. Stable compost has a ratio of around 1:20, IRRC. So you can let the fungi and bacteria chew down the carbon for a year or two recycling the native nitrogen until they burn off most of that carbon as CO2, or you can add nitrogen, which the fungi will lock into the carbon. Simple high urea yard fertilizer works well, and quickly. In a few months, with occasional watering and turning, your wood chip pile will be chocolate brown from the Maillard reaction as the nitrogen binds with the lignin in the wood chips (just like the structure of humus molecules). It happens without the fungi but needs the heat. The fungi do something with the same result though.

Now you have a natural slow release nitrogen source for your garden and you can mix it in as deep as you want and watch the mushrooms pop up out of the soil all summer long. I did this with a wood chip pile started in December and mixed it into clay in the spring. It cooked under the snow all winter. I mixed five inches of wood chips into about nine inches of hard clay each of two years. No tiller, just a lot of work with a shovel (but a tiller would have been soooo much easier). The first year you can grow agressive plants like tomatoes well, but stay away from things with wimpy roots. Shallots and peppers did not do well. Better yet, grow a cover crop of winter rye and then dig that in at the end of the year. The second season you will have good dark soil. Plant roots help break up clay clods a very little bit so you will need a tiller to mince them up if you ever want to get away from them.

Note that humus is the product of lignin and nitrogen, not cellulose and nitrogen. Wood is mostly lignin, most compost materials are high in cellulose. They get eaten by woms and the carbon is gone in a couple of years. Lignin based humics stay in the soil for ten to fifteen years.


Ruining the soil by tilling is a partial myth for gardeners. Farmers in early modern times fertilized heavily and tilled heavily spring and fall, and over twenty years the soil bacteria took over from fungi and consumed all of the soil carbon out of the fields. It took decades to deplete good farm soil. Cover crops, which put a lot of carbon back into that ruined soil turned it right back around.

Fungi grow fast if they have food. Food equals compost/dead plant matter. And if the fungi have that food they will take mineral fertilizers (the evil poisonous blue stuff,) suck it up, turn it into fungus flesh, and when they die it will be released as 'natural' fertilizer.


Tilling soil with no compost and a lot of mineral fertilizer will eventually deplete your soil down to clay and sand, and create a hard pan at the depth that your tiller digs. So don't do that year after year growing the same plants in the same spot.

If you have uncomposted wood chips, put them on top as a mulch to stop weed growth. They won't do much fast for your soil though, but growing the fungi in the soil instead of in the compost pile is much much better for the soil texture du to substances tht the fungi exude. Mix in half composted material and live with a substandard garden for the first season for max benefit in the future.

If you want to be organic, mix your wood chips with a truckload of alfalfa for the nitrogen, or fish meal if you don't mind raping the ocean, or road kill (my favorite), Feather work well if you can find them but take time.

My 2 cents.

[Gary350]

I would use the tiller. It will give you a good mix and it is easier and faster.

[rainbowgardener]

Nice post, TZ, very informative.

[TheWaterbug]

In a few months, with occasional watering and turning, your wood chip pile will be chocolate brown from the Maillard reaction as the nitrogen binds with the lignin in the wood chips

Oh great. I had to look that up, and now I'm hungry.

(just like the structure of humus molecules). It happens without the fungi but needs the heat. The fungi do something with the same result though.

Now you have a natural slow release nitrogen source for your garden and you can mix it in as deep as you want and watch the mushrooms pop up out of the soil all summer long. I did this with a wood chip pile started in December and mixed it into clay in the spring.

I'm curious; what does everyone think about this municipal mulch from San Pedro:



The shiny thing is a quarter dollar, for scale, but it's washed out by my flash.

Is that going to tie up a ton of nitrogen if I mix it into my soil? It's steaming and it smells mulchy when I shovel it, but it's pretty coarse relative to finished compost.

Should I cook it for a few months first? Or should I just use it strictly as mulch and turn it in at the end of the season?

On a related note, every single planting guide I've ever seen says "mix in plenty of organic material," but they never address the issue of N lockup. How "ready" are things like bagged garden soil and similar products for tilling in?

The very little true compost I've seen tends to be much finer and more decomposed than any of the bagged stuff I see in stores.

Cover crops, which put a lot of carbon back into that ruined soil turned it right back around.

I've been thinking about cover crops, especially now that I have a tiller. Any suggestions for deep-rooted cover crops that will thrive in a Los Angeles winter? We get cool, but never cold (seldom ever below 40 F), and we get a little bit of rain.

I have the tiller, but I lack a mower. Can I just run the tiller and plow a typical cover crop right under? Or am I just going to foul my tines and spend my day swearing at it?

Or should I get a weed whacker and take it all down in a few passes, a few inches at a time, and then till it in?

Do the right cover crops also exhibit N lockup while they decompose? Or are they net N contributors right away?

Or should we just have a separate cover crop thread?

[ReptileAddiction]

Your mulch, Waterbug, looks a lot like the bagged compost I just bought. Do you thinjk mine will tie up nitrogen if I mix it into my mix for my container tomatos? This is a close shot so things look bigger than they are in real life.



If it helps for reference that is my finger in the top left corner. I have fairly thin long fingers.

[digitS']

It surprises me what is sold as topsoil these days. There seems to be an awful lot of wood in the material! But, that's "topsoil."

My environment isn't much like southern California. I don't think I'd worry very much about tying up nitrogen with the material in either picture. One thing, if you soil already has good N levels and a lot of active microbes in it, they can move into the new material and decomposition can be quicker. Certainly, you have the warmth and I'd think that dryness could be a greater problem.

You can get into trouble with cover crops. I've had something of a mess trying to kill small, winter rye plants. The way I found that was easier to deal with them is just to grow the winter rye as a "compost crop." Allowing it to grow to a good height, pulling it by hand and getting it off the soil surface was easier than trying to till in the plants. I should say that running a big tiller over small plants wasn't difficult but having to do it 3 times over as many weeks because many of them didn't die, wasn't much fun.

Most of the nitrogen in a plant is either in the seeds or the chlorophyll, as best as I understand. When the plant material dies and loses its green color, it is not only losing pigment, it is losing nitrogen into the air. Straw is coarse and low in N. If green grass can be kept exposed to oxygen after it has been cut, quite a bit of the nitrogen that is in it will be retained in the compost/soil.

Not all carbs are created equal. Coarse straw like coarse wood won't decay quickly. Moisture dense and sugary roots can decompose fairly quickly and thoroughly.

I am wondering if fava beans would be a good winter cover crop for southern California. That would probably be a good place for your weed whacker, Waterbug. When I have grown fava beans, the plants have decomposed very quickly after they were killed but I think it would be best to take a couple of passes thru them to chop them up in short pieces and then till them in.

Just some thoughts . . .

Steve

[TheWaterbug]

Your mulch, Waterbug, looks a lot like the bagged compost I just bought.

How much did you pay for that, and where did you buy it?

I got the free stuff at the Los Angeles S.A.F.E. Collection Facility.

You have to bring your own bags or barrels to take the stuff away. I use these Demo Bags, which work pretty well.

[TheWaterbug]

I don't think I'd worry very much about tying up nitrogen with the material in either picture. One thing, if you soil already has good N levels and a lot of active microbes in it, they can move into the new material and decomposition can be quicker. Certainly, you have the warmth and I'd think that dryness could be a greater problem.

So if I till it in with some powdered nitrogen fertilizer and keep it moist, it should be fine?

You can get into trouble with cover crops. I've had something of a mess trying to kill small, winter rye plants. The way I found that was easier to deal with them is just to grow the winter rye as a "compost crop." Allowing it to grow to a good height, pulling it by hand and getting it off the soil surface was easier than trying to till in the plants. I should say that running a big tiller over small plants wasn't difficult but having to do it 3 times over as many weeks because many of them didn't die, wasn't much fun.

I do this already with my weeds, so I'd be happier if I were doing it with something more beneficial

I am wondering if fava beans would be a good winter cover crop for southern California. That would probably be a good place for your weed whacker, Waterbug. When I have grown fava beans, the plants have decomposed very quickly after they were killed but I think it would be best to take a couple of passes thru them to chop them up in short pieces and then till them in.

And a nice Chianti

I'm willing to try a cover crop once, just to see if/how it works.

Thanks for the ideas!

[TZ -OH6]

Some ramblings before my morning cofee.

A well composted pile of wood chips will sink to about half the size it was, be chocolate brown color, have mushrooms sprouting from it, and not have any stringy bits left. The stringy bits break down into little crumbly bits before the bigger chips, so if they are not broken down there is still more work for the microbes to do. If there is still structure in the wood that resists when you try to beak it up there is still cellulose and lignin that the fungi and bacteria can chew on. Mushrooms are a good clue since the fungi will grow as long as they can before sending up fruiting bodies. When they are finished they put up mushrooms.

I don't know how some potting mixes/soils get away with having so much wood in them, but I suspect that they have 'starter' fertilizer added and the peat content helps.


A note on using beans for a cover crop. (I don't know if this holds for favas as much as American beans _H. vulgare_).

1) Beans are terrible nitrogen fixers as far as legumes go. They act just like any other plant and won't do well in poor soil. So its smarter to go with proven high impact crops like vetch or alfalfa.

2) Legumes do not develop root nodules and fix nitrogen if they have nitrogen in the soil to use for growth. The soil must be nitrogen deficient for them to do their thing, so in many cases, growing rye to scavenge left over 'fertilizer' before it leaches away is doing the same thing vetch is since most gardens are not managed to the nutrient edge like farms are.

3) You have to plow under your legume cover crop and let it rot to release the nitrogen back into the soil. Growing soybeans and then harvesting the beans isn't helping the soil a great deal since you are walking away with the bulk of the nitrogen.

Related

4) The idea of Native American 'three sisters' gardening as being self sustaining for soil fertility is B.S. Native Americans got two good years and one bad year out of a field, and then they switched to a field that had been sitting fallow for several years. As the soil rested, bluegreen alge fixed nitrogen and put it back into the soil. Snow added some, as did lightening strikes.

As far a human diet went, corn beans and squash, with a little venison or bison meat added, made the North American natives the tallest healthiest people on the planet at the time (1800s).

[imafan26]

Organic matter that is not fully composted continues to be degraded. It won't be finished until it can no longer be recognizable as the original source material and you also don't see as much of the actinomycetes in the soil. As to when it is released. It largely depends on the death of the soil organisms. Most of the nitrogen is stored in their bodies and is released when they die and are consumed by other organisms. Some soil organisms will fix nitrogen and make it available to plants, others release nitrogen back to the atmosphere. Where it cycles again.

"The world is a circle without an end. Nobody knows where the circle begins"

https://soils.usda.gov/sqi/concepts/soil ... d_web.html

Cinder is what we have readily available here. It is basically crushed lava rock. It is heavy, but a lot easier and cheaper to get than perlite in quantity. Coarse sand would be the other thing to use. A lot of the sand here is beach sand and it would not be good for the soil to add the salt and it is even heavier than cinder.

Cinder is sometimes used for pathways, and in construction. It is a porous igneous rock(lava) with many fine holes and a large surface area. It can be very abrasive. It does not really compact or breakdown quickly and the irregular surface helps break up the clay particles and helps to aerate the soil. Cinder comes in different sizes. It is pretty much crushed lava rock. It has helped the soil drain faster. Medium cinder can be used as orchid media. It is heavy and contains no nutrients, but provides excellent aeration. drains, and dries well.

When I add compost, green manure, or mulch to the soil it makes the already wet soil hold on to more water. Over time it compacts as the mulch decays. The soil ends up being heavy, sticky, difficult to work, and remains wet for long periods of time. Plants are short and need to have supplemental nitrogen or sometimes the plants will be stunted and the leaves will yellow. The soil actually has puddles of water that will last for days.

Beans like a lot of nitrogen, inoculating will increase nitrogen fixing nodules on the roots. All beans are not created equal. The most common bean for green manures are cowpeas, pigeon peas, hyacinth bean, and sun hemp.

For a green manure to be maximized, the soil needs to have organic matter, the beans should be inoculated with the proper inoculant which in most cases is the cowpea inoculant. The cover crop is planted thickly and turned under at peak flowering. If the beans are allowed to form and they are eaten, then most of the nitrogen went into the pods. You will be adding mostly biomass. If you use synthetic sources of nitrogen you will not get that much nitrogen fixing nodules because all organisms take the path of least resistance. If the plants and bacteria have a ready source of nitrogen they have no incentive to waste energy making their own.

Hairy vetch is an excellent manure. I used buckwheat, cowpea, sunhemp and alfalfa mainly because the seed was easier to get locally. I can get cow pea from almost any seed rack or grocery store. I can get most of the other seeds as sprouting seeds from the health food stores. We save sunhemp seeds whenever it is grown. (It is also has nematocidal properties). The inoculant was the hardest thing to get. I had to order it on line.

[imafan26]

I was researching what constitutes loam.

Most recommend continuing to add organic matter to the soil to improve it.
When I looked up soil. It said loam soil is 40% sand 40% silt 20% clay. Loam is considered the ideal soil that is nutrient rich, holds on to some water, drains well and is relatively easy to work

Clay loam is 30% clay. Adding organic matter improves workability of clay soils, holds on to water for a long time.

Most sites do not recommend adding sand or perlite at all since such large quantities would have to be incorporated to make a real difference and it would not be cost effective. Smaller quantities can actually make matters worse as they will fill up air spaces.

The best advice I could find online was to:
1. continue adding organic matter
2. Use the garden fork to loosen soil rather than till heavily. This is to promote aeration without damaging soil structure. Earthworms will do most of the tilling and aeration for you.
3. Stop over watering. Clay loams fortified with organic matter hold on to a lot of water. The top may appear dry but the soil below may not be. If the plants aren't wilting, they can go a little longer.

P.S. I should be doing this too.

https://counties.cce.cornell.edu/schenec ... ntings.pdf
https://www.hort.purdue.edu/ext/loam.html

[Dillbert]

ima -

do note, sand - clay - silt
these are all non-organic substances and are "different" in particle size, shape and mineral composition.

it is entirely possible to take a bucket of sand, add the "proper" proportions of silt and clay and get an absolutely correct soil = loam.

I suspect you've found this kind of info:
https://www.oneplan.org/Water/soil-triangle.asp

when a soil scientist analyzes a sample, the first thing they do is put the sample in a high temperature oven to burn off any organic matter.

lots of organic material in soil is a good thing. 10-15% by (dry) weight is a good target. but again one needs to understand how these "measurements" are made - if you send in a soil sample with tree limbs included - they get sifted out before any testing even starts. "wood chips" in soil will not be included in the final % analysis.

whether to add sand is not an organic matter issue - adding sand, in amounts sufficient to "cross a boundary" will by definition change the soil structure.

the actual danger to adding sand is in a heavy clay - adding some but not enough can result in a harder, less permeable soil than one started with.

[imafan26]

Dilbert. You are absolutely right that is what I found out.

The labs do test soil with a settling test for percentages of sand, silt, and clay.

If a soil test is properly taken, there should not be that much organic matter in it. the soil should be taken from the root zone 3-7 inches deep to exclude mulch and whatever just sits on the surface of the soil.

Particle size does matter when adding sand to clay soils. It would probably also be costly. Not any sand will do, it has to be large particle coarse sand and 50%-75% by volume of the soil would need to be added. Insufficient amounts of sand would take up the air space and the soil would be akin to cement.

Interesting though, cinders are not that bad to add to the soil as long as you don't walk on it. It helps with drainage and aeration because the particles are large, porous, and they are a source of minerals. Rock dust can be made from crushed basalt. Black cinders are lava rock cinders.

I have successfully grown orchids, anthuriums and citrus trees in black cinders for years. One of my citrus trees has been in the same pot of cinders for 14 years. I have found that the secret to longevity of plants in pots is aeration. Cinders do that very well.

I also know that ideal soil is 5% organic 45% mineral (sand/silt/clay), 25% air 25% water.

The ratio's are important. The composition of the mineral part of the soil determines in the most part pH, how well the soil utilizes nutrients and holds or drains water. Most of the minerals that plants need come from the minerals stored in the soil.

Plants can live without soil if nutrients, air, water and root anchorage are provided.

However, most plants cannot survive in pure organic matter very long. They need access to the minerals, support, and balance that the soil provides. That is why organic matter is worked into the top few inches of the soil, but the roots of the plant will go down deeper into the soil layers if air, water, and nutrients are available.

If that soil layer is poorly drained, lacks air spaces or is impervious to water and roots, most plants will start to show signs of trouble when the roots get there.