How to Permanently Improve Your Sandy Soil

Size of a pumpkin leaf: 42 cm, that’s 16.5″. Not bad for a sandy soil!

One of the problems a lot of people have is how to improve the fertility of sandy soil. One solution is to add more organic matter (compost, manure, wood chips), but unfortunately if you live in a hot and humid climate the stuff you put in the soil is going to decompose quickly, since microbial activity is so fast. That creates a serious problem, because your poor sandy soil is not holding nutrients. You can add fertilizers, but they are going to leech out of your soil very fast. Because of that your fruit trees, shrubs, and vines will be yielding poorly, and they will be susceptible to diseases and pest damage. What’s worse, the fruits (and vegetables) of your labor will taste plain and they will not have a lot of vitamins and minerals in them.


How can sandy soil be improved?

What you need to do is increase the capacity of your soil to hold nutrients. Then adding fertilizers (either organic or not) will be much more effective, because the stuff you put in your soil will actually stay there. As I mentioned before, compost or mulch are sometimes not the best option because they’re often decomposed very quickly. But there is a way to permanently improve the organic matter content of your soil. It’s called biochar.

What is biochar?

Biochar is a fancy name for charcoal if it’s used as a soil amendment (to improve soil properties).

The benefits of using biochar

Its main benefits are:

  • Significantly and permanently increasing soil Cation Exchange Capacity (CEC) — i.e. the soil’s ability to hold nutrients
  • Because of its high porosity it creates lot of habitats for beneficial microbes
  • Increased water retention

How is biochar made?

Usually biochar is made of agricultural wastes, such as stalks, straw, and wood of no commercial value. Sometimes it is made of manure or animal bones. If it is made of manure or bones, its immediate fertilizing value is higher, but it will not be as permanent. Biochar made of wood or woody organic matter should not be considered as a source of nutrients for the soil since its purpose is not to fertilize your plants or soil, but to create the opportunities for it to be fertile.

It’s mainly used by farmers or gardeners who follow sustainable agriculture practices.

Why should you use biochar in your garden or on your farm?

There are reasons to believe that biochar is responsible for the existence of terra preta. It’s a type of soil that was probably created by Native Americans in the Amazon Basin. It was created by mixing charcoal with waste (manure, bones, food waste, human feces, broken clay pots, etc.).

How fertile is terra preta?

Researchers have measured the CEC of “fresh” biochar made from pine sawdust pellets and pine timber ranging from 22meq to 138meq. (Characterization and Comparison of Biochar, Herbert et al, CalPoly2012). It is also known that as biochar ages its exchange capacity can increase, up to an order of magnitude (10x). In 2006 researchers compared several ancient char-amended soils (terra preta androsols) in the central Amazon with adjacent soils to which char had not been added. The most impressive result was an androsol with an Effective CEC of 213meq compared to adjacent soil with an ECEC of 23meq. This same androsol, estimated to be 600 to 1000 years old, tested as containing 9064ppm Phosphorus and 17 545ppm Calcium, vs the adjacent soil with only 273ppm P and 115ppm Ca. (Black Carbon Increases CEC in Soils, B Liang et al, Soil Sci. Soc. Am. J. 70:1719–1730, 2006) — Ideal Soil 2nd edition, by Michael Astera

By comparison, poor, sandy soil with little to no organic matter would have a Cation Exchange Capacity (the ability to hold positively charged soil nutrients) in the range 1-4.

Corn grown on soil with and without biochar. Terra Preta on your right.

Because of its unusual ability to hold nutrients, it was and still is very fertile….

It’s a remarkably fertile soil, which is rich in organic matter. What’s so unusual about it? There are other places in the world that have soils with high organic matter content. That’s true, but most of those places are in much cooler climates. Because of high microbial activity (both heat and moisture) all “normal” organic matter is quickly decomposed, so it’s almost impossible to bring the soil up to 2% organic matter content.

The term “organic matter” means matter containing carbon (C). What’s unique to biochar is the fact that it’s a type of organic matter that no living things (except for humans — i.e. if we have food poisoning) want to eat. So if biochar is added to the soil it tends to stay there, especially if no till agriculture is being practiced. It’s a good thing to do if you have a lot of brush or decaying wood to clear – you might get rid of weeds and improve your soil in the same time, changing a problem into a solution….

What do you do if you don’t have any brush or weeds to clear?

What do you do if you can’t make charcoal?

What do you do if you don’t want to make charcoal?

The obvious solution is to buy charcoal! But that might be expensive and usually the wood that’s used to make charcoal is acquired by cutting the tropical jungle somewhere in Southeast Asia. That means it is not too good for the environment…. Fortunately there’s a different type of carbon product that microbes can’t consume.

It’s coal.

Yep, that black stuff that’s being mined from the ground.

How do you make biochar to create terra preta?

Because of that we (by we I mean myself and Jacek Kobus) decided to check how good coal mixed with horse manure is in improving properties of the sandy soil. Jacek created an impressive pile of horse dung mixed with culm (brown coal dust). Culm is the cheapest fraction of coal you can buy. We bought 1 ton of culm and then mixed it with 3 parts – by volume – of horse manure.

Biochar made the Polish way – culm (brown coal dust) mixed with horse manure.

Why does biochar research sometimes show a decrease of yields?

I mentioned before that biochar is not a source of nutrients for your garden. The same can be said about coal. Although it contains a lot of micronutrients and trace elements, but they are not available for plants.

What’s more important to remember is the fact that coal or biochar has both a high Cation Exchange Capacity and Anion Exchange Capacity. That means it can hold all sorts of nutrients for plants very well – that’s why you want to use it in the first place! But most of the “place” where the nutrients can be held is initially empty, waiting to be filled up.

Because of that, if you apply it to your garden, field, or pasture straight away, it would suck up and hold nutrients from your soil. If you have infertile, sandy soil, your biochar will be taking and holding nutrients from your soil for months, making the growth of your fruit, vegetables, and cereal less than perfect. That’s why biochar research sometimes shows a decrease of yields after an application of biochar to the soil.

How do you charge your biochar with nutrients before applying it in the garden?

Mixing biochar with manure – “the dry method”

It’s quite simple – just mix your charcoal or coal with some moist animal manure and let it “mature” for at least 2-3 weeks. We used 1 part coal dust to 3 parts horse manure, because that’s what was available. You can also use chicken, pig, or cow manure.

Mixing biochar with urine or another liquid in a barrel or container

Some people also put coal into a barrel, then add urine or any other liquid fertilizer so the coal can “suck up” nitrogen, a bit of potassium, phosphorus, and other trace nutrients that can be found in human urine or a different fertilizer. Again, let it “rest” for at least 2-3 weeks before you apply it to the soil.

One of my readers used a similar method to prepare special biochar for blueberries – he mixed coal dust, sawdust with water, elemental sulfur, and ammonia sulfate to make biochar more acidic.

The results of using biochar made of coal on sandy soil? It’s actually quite impressive….

20 year old cat hunting for rodents in biochar fertilized field of pumpkins

How do you add biology to your biochar to improve the soil food web?

Before you apply “nutrient charged” biochar to the soil you can add some beneficial organism (microbes, mycorrhizal fungi mycelium or mycorrhizal fungi spores) that will improve the biology of your soil even further.

Using biochar as animal bedding

You can also use biochar as the bottom layer of animal bedding. It will soak up excess liquid, tie up nutrients, and limit nitrogen loss. You can also add some rock dust (like granite rock dust or basalt rock dust) to your biochar. Just make sure to add some other bedding material on top of it, like straw, wood chips, or sawdust.

Should you mix biochar with rock dust or not?

If you are planning to add rock dust to your soil, you can add it to the charcoal-manure mixture. It is especially beneficial to mix soft phosphate rock dust with manure, because microbes from manure will help to unlock nutrients from phosphate rock.

Should you dig biochar into the soil?

I advise incorporating biochar into the soil but it will work even if you spread it on top of your soil. Eventually it will get into the deeper soil levels.

If you want to spread it on top of your soil in your garden it will be good if you put some mulch made of “normal” organic matter that will be digested by microbes.

How much biochar should I add to my soil?

Biochar is one of those things that the more you have in your soil, the better it is, but the minimum value I recommend to use in a garden is a 1″ (2.5cm) layer on top of your soil. No matter if you dig it in or not, you will have more than 10% organic matter content in the top 6-8″. If you add 2″, then even after the manure that you mixed with your biochar decomposes, you will still have plenty of organic matter in your soil. That way you can have a Cation Exchange Capacity for your soil from 1-4 to 8-12, which is good enough to grow high quality, nutrient-dense fruits and vegetables. Our pile made of 1 ton of coal dust and 3x as much horse manure was enough to cover 300-400 m² (3200-4200 square feet or 1/12 of an acre) with 5cm (2″) layer of biochar mixed with horse manure.



56 thoughts on “How to Permanently Improve Your Sandy Soil

  1. Love what you’re doing, but stop thinking about commercial value….

    everything in this world is 100% free.

    I posted a few ads on gumtree looking for farm land for organic permaculture to
    feed the community for free.
    in under 2 weeks 9 offers had bee made totaling about 3,000 acres…all for free.
    then i put the word out on facebook for people to help out
    and received offers from 30+ gardeners and hippies and light beings of
    all walks.
    Even a bulk Organic Seed company looks likely to come on board.

    All for free….no irrigation needed, simply observe natures methods and help her along.

    if you would like to know more, contact me on facebook ‘unconditional love moon’



  2. How I try to improve our Sandy Soil.
    Identify paths and try to put woodchips in paths.
    Any large logs over 4inch thick are laid as a border along paths and creatings beds.
    The Logs will encourage fungal activity for trees to be planted later and mushrooms have flourished. It has also created “edges”
    Spread leaves all over to preserve soil moisture and increase soil organic matter.
    Coppice some trees such as Leucaeana and chip the small twigs, Char the bigger branches and use the thick trunks for borders.
    The char is added to compost after soaking , but some have been added directly to planting holes after soaking with compost tea.
    The edges created by logs as well as the mulch has increased habitat for bugs and that has attacted many more birds.
    A groundcover of Cowpeas and some Sweet Potato will be planted this season to cycle the nutrients even further and keeping soil and mulch cool .
    Cant wait for the first rains !

  3. Great article that brings me one step closer to actually trying out biochar myself. Perhaps you can provide two extra bits of information:

    1. I plan to use biochar in a forest setting. I’ve got a former pine plantation on poor ex-heath soil that’s been overgrazed for several centuries. It’s now being overrun with black cherry, but due to the poor soil the cherry is growing awfully crooked. So I want to use biochar on a full hectare (100×100 meters, that’s about 300×300 feet). Any tips for large scale-application in a soil that’s already full of tree roots?

    2. I can get the horse manure for free. But what’s the price you paid for the culm?

    Best regards!

    1. Hi Wytze,
      What sort of climate and soil are you dealing with?
      Have you done a soil analysis in recent past?
      What’s the ultimate objective you want to achieve by using biochar?

      To be honest biochar might not be the most cost effective way of improving your soil. What you are describing (crooked growth of trees) might be “just” multiple deficiencies and/or in macro, micronutrients and trace minerals.

      2. The price of culm was around 330 zł, that’s approximately 110 US $. A big chunk of the price are taxes (EU). As culm is somehow difficult to burn (you need a special furnace to burn it efficiently) it cost less than 50% of coal sold in nice, big chunks. The price I mention do not include transport.

    2. One of the things to check when using manure is to ensure that the animals have not been treated for worms as this would make the soil uninhabitable for worms that play an important role in your soil. The exception is the use of copper for treating worms in goats.

    1. @Igor
      I appreciate your concerns. Coal dust is indeed unhealthy to breath in. If you do it for many hours a day, for many years (as a coal miner). During preparation of biochar one might use simple mask or sprinkle coal dust with water, so it won’t be dusty for a moment. Jacek was mixing culm with horse manure during late winter, so it was quite rainy and dust was always moist.

      1. Hi Wojciech,

        Thanks for your answer.

        I’m in the Netherlands. The soil for the first few meters is rather fine, iron-poor sand and it’s uphill, so the water table is very low (unreachable for trees). It’s been heath until around 1900 (with the nutrients grazed off and leached downward), was then plowed to remove the hardpan at 50cm depth, and has been a pine plantation since.

        The crookedness may in part be due to a lack of multiple micronutrients, but also due to a very thin, acidic soil that is easily dried out and that can’t hold the nutrients released by decaying pine needles etc. It would really help if the soil were to retain more moisture, thus hold more life, thus cycle more nutrients. Biochar seems to fit in that respect.

        My goal is to stop the pine monoculture, to have more diversity, but for economic purposes we do need to harvest and sell the trees that grow there, which means in practice that they need to be a lot straighter (and grow somewhat taller) than the current batch of black cherry.

        So far, this piece of land can only be used to grow value if we stay stuck in a cycle of poisoning the cherry, waiting for pine to regenerate, protecting the pine from regenerating cherry in the first years, thinning the pine as it gets older, until the cherry comes popping up again, etc

        Insane huh?

        Thanks for the price! $110 for a ton of culm sounds manageable, although you’re right that it’s likely not to be the best choice on a large (hectare) scale.

        Thanks again,


        1. Yeah, that sounds like a challenge…Maybe if you fix soil deficiencies and plant blueberries on contour with mound of biochar mixed with manure etc… You might be able to justify the high cost of biochar application.

          In your conditions (soil with poor nutrient holding capacity) rock dust might be good if you find some cheap, local source. It ill release nutrients slowly. Basalt rock dust would be the best, as it has a bit of calcium and magnesium too.
          For phosphorus phosphate rock dust or bone meal would be spot on, as they are not easily to leach out.

          My friend Jacek will get a truckload (25tones) of marble dust. It’s pretty much very slow release lime or dolomite lime (difficult to say without analysis) with a bit of other nutrients in it. Great addition to his sandy, acidic pasture. As love moon said you can get some stuff for free (Jacek did I think). Ask in the places they produce monuments, tombstones, stone kitchen worktops etc. as they usually have to pay to have the stuff dumped in the landfill.

        2. Hi All – Wytze – you may find Sepp Holzer’s Permaculture: A Practical Guide to Small-Scale, Integrative Farming and Gardening Paperback – April 11, 2011 a VERY USEFUL guide. He’s in Austria – high altitude; land originally monoculture pines; spruce and was able to transform old timberland/monocultures into a vibrant permaculture along with a successful, profitable enterprise for his family. He talks about all the same issues you have described, and how he solved obstacles with climate, terrain, soil texture, nutrients. If you are not familiar with his work – I think you will find it enlightening. He also provides limited conferences a few times a year for farmers & landowners, and I think he has worked with someone in the Netherlands (so resources would be closer to home for you!). Thanks again for all that everyone has contributed here (I’m from one of those hot, humid places – north Florida, USA….

        3. Hey mate,

          Have you tried putting in a series of swales on contour.. this will slow the movement of water on the hill side and allow nutrients to stay where they are. You could even incorporate Hugelculture (probably wrong spelling) at the swale edges to further enrich the soil and slow down the amazing decaying elements. Use the branches that you prune for this.

  4. I’m using Bio-char in my soil which is a Franciscan Clay. It has done wonders for the soil and along with wood chips under my fruit trees has made the flavor of the fruit outstanding. With the drought here in California it has made a big difference in my soils capacity to hold and retain water. Wytze could be using thinning wood from the pines or trimmed lower branches for making the bio-char. I’m using mulberry for making mine an using only the trimmings from the tree.

  5. Hi Wojciech,
    thanks for your article!
    Are you referring to Poland by describing the climate “hot and humid” or are you thinking of the tropics?
    In the Amazonian jungle all the nutrients are recycled really very fast. What about planting fast growing trees which can spend shade and decrease air temperature by transpiration as fast as the decomposing process works?

    You mentioned the soil food web. So i assume you heard of Mrs. Elaine Ingham. She says that all soils in all countries in the world holds all the nutrients plants need to grow (It’s from a yahoo discussion group which needs sign-up):

    Message 1 of 49, Aug 27, 2004
    Teaching the Soil Biology and Soil Chemistry course with Dr. [Graham] Lancaster here at Southern Cross University, and we are showing some very interesting relationships between soil chem and soil biol.
    Did you know that NO AGRICULTURAL SOIL lacks the NUTRIENTS needed to grow plants?
    Maybe one or two rare exceptions to that rule when we get into non-ag [agriculture] soils, but any soil used for agriculture does not lack the nutrients needed for plant growth.
    So, why do we add fertilizers?
    Because the AVAILABLE nutrients may be limited.

    But no one needs to add inorganic fertilizer to their soil, unless they lack the biology that should be there. When you look at total nutrients present in any soil, there’s more than adequate levels in any ag soil.
    We calculated how many years’ worth of phosphate was actually present in wheat filed soil in Australian, soils where growers have been told they needed to add thousands of dollars of PO4 because there was no phophate present. There was 15,000 years worth of phosphate present in that soil (something like $48,000 worth of “fertilizer”), if that phosphate could be made available to the plants.
    or if it is not possible to enter this group here is german forum which holds a lot of information about Mrs. Ingham:

    1. Hi Stephan,

      I was referring to tropics when I was writing “hot and humid”, though Poland and I believe Germany was like this this summer!

      Planting trees in tropical climate will decrease soil temperature (compering to the open field), but it will not be enough to allow significant accumulation of organic matter in the soil. It’s still too hot and too humid. You don’t get soils high in organic matter even in rainforest that wasn’t burn for 500 years.

      I do agree, that in most cases you have enough nutrients to “grow” plants. But it’s usually not the case if you want to grow high quality, nutrient dense food. You simply need certain balance of nutrients available in the soil. You can add tons of good quality compost, compost tea, but it will not make nutrients available in the right balance if they are not in some sort of balance in the soil. I’ve eaten plenty of poor quality organic produce food in my life (and I’m not saying that organic grower use Mrs. Ingham’s methods, but as they do not use pesticides, they soil should be somehow better.

      Now, I am not hating on soil biology, it’s very important, as it’s making nutrients more “digestible” for plants. But it’s one component.

    2. Optimum nutrients in the proper proportions made available to plants results in optimum yields and quality of crops. Ongoing research and results substantiating particulars from many sites are ongoing and shared at:

  6. Part II

    Here is another Yahoo discussion group (also with sign-up needed, ) about the presentation of Mrs. Ingham at the Permaculture Voices conference this march:

    FW: Dr. Elaine Ingham at the Permaculture Voices conference
    Dennis and Mary
    Message 1 of 70 , Mar 20

    At the end of her keynote lecture I had the opportunity to talk to her directly. I asked her that if all soils have all the minerals needed for life, why is it that my soil tests come back with different data using Mehlich III, which is a strong acid extract. She said that Mehlich lll was not that strong. To extract all the minerals from soil you have to use a very strong acid. I think she said 25 molar hydrochloric acid. When you use that, the data from all soils is essentially the same. She showed a chart with percentages of minerals in any soil during her lecture.

    I think Mrs. Ingham meant something like Agua regia or nitro-hydrochloric acid ( Bacteria or fungi are capable of producing such acids by themselves. But without this microorganisms it is impossible to leach out all the nutrients in a soil, which is said about the Laterite soil in the amazonian jungle.

    Two other famous soil scientists were Raoul Francé and his wife Annie Francé-Harrar. They discovered all the things relating to soil biology in the 30s and 40s of the last century. Here are some books and texts of them:

    They describe, like Mrs. Ingham, how all these microorganisms (bacteria and fungis) are able to hold all the nutrients needed by the plants by working together (in themselves or in a solution around them).

    1. @Stephan
      Part 2
      Sorry for the delay with answering to part 2 of your comment, I was talking with my customer…

      Thanks for the interesting links. I must agree with most guys there – how can your plants be well nourished if the soil it’s grown lack certain minerals?

      I will translate a certain information from internet encyclopedia:
      “In 1932 15% of conscripted men from Podkarpacie region (in Poland) had goiter. Since 1930 iodine was started to be added to the salt, to prevent goiter. In 1938 only 2,9% of conscripted men from Podkarpacie region had goiter.
      During WWII iodine was not added to the salt and as a result 37% of people in Myślenicki county and Nowy Sącz county developed goiter.”
      Now to give you a perspective… People in that area were doing organic agriculture. They were not using artificial fertilizers or ag. chemicals as they simply couldn’t afford them. Yeah, they were not using compost teas, but every bit of manure was returned to the fields, crop rotation was being practiced. They were eating locally. If anything they were eating even more locally during WWII as they probably could not afford to buy salted herring (traditional Polish food), so nutritional imbalances and deficiencies caused by the soil were made even more profound.

      Still it’s not good enough to prevent goiter if you are not supplementing iodine. Why? Because this element is not present in sandy soil made of granite in large enough amounts.

      1. @Wojciech Majda

        Again with two parts, because it would be too large in one post.

        how can your plants be well nourished if the soil it’s grown lack certain minerals?

        That’s what i thought half a year ago too. One official truth regarding e.g. phosphor is: The only real source (beside faeces of man and animals) in the world is apatite (a group of phosphate minerals: Ca5[(F,Cl,OH)|(PO4)3]]: ) which is only found in mineable quantities in certain regions in the world.
        The real truth is: There are hundreds(100s!)of minerals containing phosphor:

        Phosphate minerals

        I know that a lot of farmers already know this. From them i learned eight years ago (when i wasn’t really aware of this incredible truth), that they are steadily asking how they can transform e.g. into a plant available form.

        The only question is not: Where is my next fertilizer shop, but how can i bring the necessary helpers (the microorgansims) into my soil:

        Phosphate solubilizing bacteria and their role in plant growth promotion
        Hilda Rodríguez *, Reynaldo Fraga
        The use of phosphate solubilizing bacteria as inoculants simultaneously increases P uptake by the plant and crop yield. Strains from the genera Pseudomonas, Bacillus and Rhizobium are among the most powerful phosphate solubilizers. The principal mechanism for mineral phosphate solubilization is the production of organic acids, and acid phosphatases play a major role in the mineralization of organic phosphorous in soil.

        Visual detection and even semiquantitative estimation of the phosphate solubilization ability of microorganisms have been possible using plate screening methods, which show clearing zones around the microbial colonies in media containing insoluble mineral phosphates (mostly tricalcium phosphate or hydroxyapatite) as the single P source.

        Biotechnology Advances 17 (1999) 319–339,

        Certain Bacteria are able to dissolve steel and glas. Among the first colonizers of cold lava are bacteria. Lichens colonize pure stones not soil. Why? How can forests grow and grow and give e.g. fuelwood and food without applying fertilizers?

        1. Hi Stephan,

          I didn’t notice your respond. I’m not denying that soil life can make phosphorus more available from many mineral sources – as you said there are hundreds of different minerals.

          The paper you quoted:
          “The use of phosphate solubilizing bacteria as inoculants simultaneously increases P uptake by the plant and crop yield.” But where was the phosphorus initially coming from? Thous bacteria maybe can make phosphorus more available in the soil. I’m guessing it will work the most for few years and then it will decrease, as the bacteria will make the most easily available phosphorus from minerals more available. But the nutrients are constantly exported (when the farmer is selling the products). My question is can they produce high yields of high quality crop year after year with only exporting nutrients from they soil?

          “Certain Bacteria are able to dissolve steel and glas. Among the first colonizers of cold lava are bacteria. Lichens colonize pure stones not soil. Why? How can forests grow and grow and give e.g. fuelwood and food without applying fertilizers?”

          Good you mentioned forests. Poor soils with adequate rainfall are really good at producing biomass. Not that much nutrients are required to do that. You should ask yourself a question WHY forests do not produce a lot of protein (per hectare)?

          Yes you can say bacteria and lichens are growing on rocks. I am not saying that they can’t release nutrients from the soil (or rocks) it’s just the speed is not good enough and the ratio of nutrients is not good. For example if granite is a bedrock the soil will have relatively lot of potassium and will be low in calcium, phosphorus and magnesium. And that’s not good for growing high quality plants and healthy animals and humans. It’s just not.

          Other factor you are forgetting is exporting of nutrients in most agriculture settings. Please compare how much nutrients are being lost in “natural” ecosystem per year per hectare to the amounts of nutrients that are exported from agroecosystem via selling of the crops. It’s orders of magnitude. And it should be like that! For example I want to grow the most nutrient dense food that have the most calcium, phosphorus, magnesium, zinc and trace elements. To do that you need to regular replenish your soil.

      2. Part II

        Now to give you a perspective… People in that area were doing organic agriculture.

        What did organic agriculture in these days (1930s) mean?
        A soil which is poor in microbial life usually lacks the capacities to transform big amounts of urine and feces or also dung or manure into a sound and healthy humus, which in addition is necessary for healthy plants and healthy food. If the soil steadily is drowned in manure and urine, especially in winter when temperatures and microbial life in the soil is low, he can’t repair the bad situation he suffers and so he hasn’t the ability to produce sound and healthy plants and foods.

        If anything they were eating even more locally during WWII as they probably could not afford to buy salted herring (traditional Polish food), so nutritional imbalances and deficiencies caused by the soil were made even more profound.

        Did they had no poultry or did no one bred chickens? Chickens and other poultry eat worms and bugs which again eat smaller animals, so usually chickens, which can run free, usually do not need any supplements to their food, not?

        To the Iod-Compounds or minerals i have found these (for only a part i did search for english names, if i understood the collections about the minerals correctly the number of minerals is steadily growing):

        Silveriodide (Iodargyrite/Lodite), Potassium iodide, Sodium iodide, Bortriiodide(?), Mercury iodide (HgI2, Coccinit/Hoppingit)

        Iodates (salts of iodic acid):
        Brüggenit, Dietzeit, Lautarit, Bellingerit, Salesit, Schwartzembergit, Seeligerit, Georgeericksenit

        Simple Halides (The halide minerals are compounds where a halogen ((fluorine, chlorine, iodine, and bromine)) is the main anion. ):
        Tocornalit (mixture of AgI and HgI2)

        1. It was 1930, poor region in II Polish Republic. No artificial fertilizers were used, so there was no huge amount of animal manure applied. I’m not sure about the amount of urine and feces used, but I guess they were insignificant as the yields weren’t high.

          Stephan, you are German, so you should know that during II WW nutrition of Polish people wasn’t really high on Nazi’s list of proprieties. I’m just guessing that during the war they numbers of chickens went down.

          Supplementing with minerals is a great idea. If they are locally available. If not it’s usually a good idea to fertilized with synthetic form…

  7. Thanks Wojciech – Knowledge about how nature works is invaluable to me.
    You article is great and very informative – Thanks for posting !
    Its great to see huge mushrooms after the first rains, then we know something is working.
    Look forward to reading more of your articles in the future.

  8. Well, it all sounds good and I like your efforts, but it’s not biochar if it’s made with coal, the reason to not use coal dug from the ground is toxicity , contains mercury, cadmium and is radioactive, all kinds of bad things, that’s why u should use charcoal since its not toxic, plants don’t take much damage from these things but they do suck it up, making your vegetables less healthy and maybe even dangerous, I suggest you look up why we can eat charcoal but not coal, you don’t want this stuff in your soil. I think if you have a soil sample done now you wouldn’t even be able to sell the land. You are putting your health at risk doing this.

    1. Hi Tonny. I think this may need more research. The views are conflicting. Also, it’s important to recognise that brown coal (lignite) is different from black coal.

      A couple of many examples:

      Can carbon inputs other than charcoal be used?

      The Japanese are extensively investigating the use of coal dust for promoting field fertility. Coal dust does seem to reproduce many of the positive effects of wood charcoal. The research of Siegfried Marian on the benefits of carbon incorporation, as reported in Leonard Ridzon and Charles Walters’ The Carbon Connection and The Carbon Cycle, led to the development of Ridzon’s NutriCarb product (no longer being produced), which claimed agricultural benefits very similar to those claimed for terra preta . Those who want to use coal dust for soil fertility need to make certain that the dust is from brown coal, which is more humic, and that the coal does not contain toxins. —


      Coal Dust As Manure

      In the February number of the Monthly Mr. J. A. Price, Scranton, Pa., says “he believes that coal dust will make an excellent fertilizer.” And so do I. General as the belief has previously been that coal dust and coal ashes was worthless rubbish, and of no possible good in the garden or field where vegetables are cultivated, and would be better hauled away to fill up an unsightly hole somewhere or repair the roads with, seems at last has been proved a common error.

      Of course it was admitted that its mechanical action only upon heavy clayey soils might be as beneficial as so much coarse river sand would be, yet it was very doubtful if it possessed any other value. And I confess that for many years I entertained a similar opinion, and would have willingly allowed anyone to have removed it as a nuisance glad to get rid of. Although we may long remain mistaken about many matters, sooner or later “time discloses all things,” and even the virtue of coal dust and ashes has at last been discovered, and through the pages of this magazine made known to all good men.

      Late experiments have proved to me that either on light friable loam or sandy land, even as sandy as much of New Jersey soil is, it is one of the best fertilizers I ever used. Wherever it was freely applied, either in the vegetable or flower garden, its beneficial effects were remarkable. Carrots, turnips and parsnips seemed to delight in it; while peas, beans, salsify and beets appeared to glory in it; and for such like things as potatoes, onions and tomatoes, why they, like “Pardoe’s pig, grew fat and big ” among it. And, talk of the flowers, that tasted it, oh, ” such beauties they did grow,” and did indeed “astonish the Browns” when passing by. Mount Holly, N. J. — (after arriving on the page you need to scroll down)

      1. Hi Craig,

        I think a lot of objections to using coal in the garden comes from the negatives effect that a coal ash might have. If you will be adding coal ash to the garden in the relatively high amounts, that are required for it to act as fertilizer, you are going to add a lot of heavy metals and radioactive elements. But if you are adding let’s say 10 tons of coal per ha just once? That’s not a big deal.

      2. Craig, you are 100% correct that this topic needs FURTHER research. Did you know the 2nd article that you posted was written in 1886? That article was the one that really aggravated me and I had to look into it. Let me explain, I was born and raised not very far from Scranton, Pa. That region is VERY unique in terms of “coal”. That region has Anthracite coal. There are distinct differences in “coal”. “coal” classifications even vary among what country you live in. People in that region used “cinders” and dust for years in their gardens. “cinders” are what you have left AFTER you burn the anthracite in your stoker, they are fairly light in weight but feel similar to lava rock (very porous and sharp). The region has a top layer of clay/rocks and the cinders would help open the soil in their gardens. It would also make all of that locked up nutrients in the clay available, so way back in the 1880’s it probably seemed like the “cinders” and black coal dust was what was giving the soil “fertilizer”. Flash forward to the late 1970’s and the people of the region started to understand that what they were doing was NOT a good thing. Sadly I have witnessed this 1st hand, way to much cancer, the CDC also has improper data as to cause of deaths in the region. Many of the coroners in that region use “heart attack” as cause of death when someone dies while battling cancer. I personally knew of 15 people that died under the age of 50 from colon cancer BEFORE I even turned the age of 19.

    2. Hi Tonny N,

      I agree that coal contains mercury, lead, cadmium and radioactive elements. But so do plants. The question is how much? Polish brown coal usually do not have a lot to heavy metals (similar content to the average soil content by weight). And even if it would, you have to consider how much it improves the soil and how permanently.

      For example if Jacek would import 10 tones of dry woodchips or straw, he would probably import similar amount of radioactive elements, heavy metals etc.. And I am unlikely to believe that 10 tones of straw will turn into 1 tone of stable humus (it has similar or higher CEC as mature charcoal/coal).
      The same principle apply if you import compost, food wastes, manure… There is no organic matter that is free from heavy metals, radioactive elements etc. Well maybe if you grow something in hydroponic solution, you can get it, but I guess it would be an expensive mulch.

      The same will apply if Jacek import fertility in concentrated form (and he would have to, because his soil has naturally low fertility). There is a chance that he will get mink manure for free or low price (just transport). So should he reject the idea of getting very affordable source of phosphorus, potassium, nitrogen, boron and few other elements that his land urgently needs, because there is SOME lead, mercury, and arsenic in this material? Especially, that he will be using rather low dose of this fertilizer (1-2 tones/ha).

      BTW it’s not as that coal dust that was brought to Jacek’s farm was advertised as a soil amendment. It was locally available as coal is use as energy source in Poland, so it would be burned anyway…
      It’s the same thing with fossil fuels – they are unsustainable source of energy, but you wouldn’t hesitate to use oil to fuel a digger to dig you a swale or a pond that will improve the landscape for hundreds of years.

  9. I agree with Tonny N. From a sustainability perspective, you don’t want to take materials from the lithosphere (earth’s crust) and introduce them into the biosphere. Coal is contaminated with heavy metals such as mercury which could be taken up by plants grown for food. It is a fossil fuel which must be mined with great expenditures of energy and resultant carbon emissions. Using coal as a soil amendment is totally inconsistent with permaculture principles, as well as potentially harmful to people and the environment.

  10. I have clay soil – would biochar still be a good idea?

    Also, I am near an area that just had some big forest fires a few months ago so we already have charred trees everywhere. Can I use those instead? If I do, how do I do this. Do I mix those with some manure in water and let it sit for a few weeks?

    1. Hi Sheri,

      It will help clay soil too. Originally terra preta was made in clay soil. You can use charred trees. If it’s not too heavy and time consuming to put them in the water and manure your plan sounds OK. We didn’t have to put it in water as Jacek started to make biochar in the winter, and it was raining and snowing.

  11. Thanks for the replys to my concerns using brown coal, and ive read the links kindly put up by Craig M, i was mainly suggesting adverse effects by the toxic elements, not refuting the benefits on poor/poorer/depleted/sandy/clay soils, because it does seem to help, in some cases greatly, so i went and researched it a bit more, the only real info ive found on toxic elements (that i didnt have to pay for) was a study done on rats and the toxicity of the dust in their lungs, but it did have some interesting content tables of the dust (from two unspecified mines, mine a and b) ,wich is what I/we want, this is probably not from the mine your getting yours i know, but couldnt find info to pinpoint where exactly you get it. as far as i can tell the cadmium content of brown coal is usually low so maybe not an imediate concern, especially if only applied once, And either there is not mercury in it or thats one they didnt test for, it “can” however contain large amounts of thalium and barium, relative to other elements found, depending on location, so if you have this info and they are low, then i wouldnt be concerned, then again if i where ever to use this, id probalby run a 4 year period of crops not for consumption, simply because i would gauge the risks as outwheiging the benefits, This would also require the removal of said crops to remove whatever toxic compounds where present, certain plants a better at taking up certain elements sunflowers/cadmium as an example, This however would reduce the fertility of the soil, the opposite of what we originally applied the dust for.

    I dont think the Comparison Mojclec Majda made between importing wood chips or straw is viable, unless made into charcoal, the real comparison would be charcoal vs browncoal, as you could easily help off setting the carbon imbalance by making the charcoal of wood/organic matter yourself, this wood/organic matter could be accuired on site, buying it in from fsc forest or grown on site, certainly it wouldnt be “nearly free” as the local dust as it would either require time/labour or money, but it wouldnt as Nathan pointed out, take stuff from the ltihosphere and transfer it to the biosphere, man i love those words :) Terra petra have been talked about alot, but ive never seen any info on them using brown coal dust, only charcoal/bone/waste and broken pottery.

    My attempts at finding a content table or info on “impurities” in charcoal have been futile. But the thing is that charcoal can remove toxic elements (and bind usefull elements) whereas brown coal dust will not since in a chemical sense its “full”, activated charcoal is even better at removing/holding these things, and i think that should be a large part of the thought process behind choosing between them. Lashing out at Nathan doesnt improve your stance on the matter either, as heavy machinery could be run on sustainable bio diesel or even vegetable oil with the right modifications, digging stuff from the “lithospehere” can be done with these kinds of machines but it would stil be mining a finite resource thats higly polluting at that. and yes we could go even further and start talking about the metal used to create the machines and i would reply that one could use trellis and other “clockwork” machines instead, so lets not derail down that route as it seems counter productive :)

    One could make an argument for the beneficial elements contained in brown coal, but then id refer you to your previous statement that “so do plants” the real issue here is ratios, by applying this dust, you may be adding a critical amount of poisinous elements that could harm you, more so children, again because of ratios, a child would need alot less of these elements for adverse effects than an adult not to mention smaller wildlife (thalium and barium has been used as rat poison)

    In my personal opinion; I would use this as a last resort to make my land more fertile, if all other sources where unviable, but would likely resort to (if unable to find wood/organic matter easily and sustainably) grow it myself and make the charcoal. Unless i could get a satisfactory element chart from the dust telling me that its safe. then i might.

    On a sidenote regarding the japanese trying out this as a means to improve fertility is more driven by a “Need” caused by rapid decline in their soils fertility and increase in population than a wish to do it green/sustainable/othergoodwordsforit.

    All written is subject to change (except the factual numbers) because i really like learning but i need “hard evidence” in the form of numbers to reveal the elements invovled, and not succesfull trials that show fertility and nothing about the resulting cancer in 30/40 years or the risk of leeching into aqufiers and so on.

    the page i found the content table (table 2);

  12. Abt grammtical errors in sentences are fully my fault, sry for that. Examples in my own text after rereading it for the 100th time
    1 “opposite of what we originally applied the dust for”
    not we, but you or “we would”

    2 “that one could use trellis and other “clockwork” machines instead”
    missing a “wooden” before clockwork

    and probably many others :/

  13. Tonny N,

    That’s a valid point comparing charcoal vs. brown dust in terms of importing heavy metals and radioactive elements. It’s probably true that charcoal would contain less heavy metals etc.
    But my point is still valid. Most people wouldn’t be afraid to import 10 tons of biomass (compost, horse manure, straw…) because of the amounts of heavy metals in them, but they freak out if it’s 1 tone of coal.

    And time and effort would not be enough, as the soil is (and was) extremely poor. I will give you soil analysis of the soil (before the improvement with fertilizers, horse manure…):

    pH 4,09 (very acidic, liming required)
    P2O5; 270 kg/ha (low)
    K2O 60 kg/ha (very low)
    Mg 30kg (very low)
    iron 825 ppm (low) [It’s actually extremely high level -W.M.]
    boron 0,42 ppm (low)
    manganese 61 ppm (average)
    copper 3ppm (average)
    zinc 3ppm (average)

    How do you work with that without importing nutrients (that will have some heavy metals in them)?

    Chemically speaking brown coal is not “full”. I guess you refer to it’s ability to hold onto nutrients (Cation Exchange Capacity and Anion Exchange Capacity)? It’s CEC increases with age (when you put it in the soil), as it’s surface are increase.

    I’m not lashing out on Nathan. I just asking a rhetorical question. My point was that’s a valid reason and time to use fossil fuels.

  14. Hi again :) yes you are right in that i would have to import nutrients/fertilizers to that kind of soil, but i wasnt trying to refute that, have you done an analysis of the dust as well? those would be really interresting, especially because of location specific differences. my own example shows mine A as having 1530ppm of Ti whilst Mine B “only” has 240ppm
    It does however contain mostly everything else that you do need in your particular soil. (the tables in the link also contains the ash % aso)

    I think where we differ in opnion the most is the stuff you grow after ammending the soil, i would be scared to eat anything of it for a few years if i had dust from mine A but again would probably do tests to show what the soil ppm ends up at, you are mixing it with the poor soil with a ton/acre so ppms are gonna drop, as i said, it is concerns, my initial post flamed a bit because you in your article mentions, brown coal dust, but just a bit up from that it says literally; “Its Coal, yep that black stuff thats being mined from the ground” easlily misunderstood, and i did. i would never ammend my soil with “black” coal / the arsenic, mercury, cadmium containing stuff unless i was living in a desperate desert situation and options where starvation or coal. But learning more about the brown dust, i might use that if easily avaible (yours is) and not toxic, I dont know if yours is.

    Yes i was talking about its ability to “suck nutrients/elements” CEC. if the CEC raise with age, isnt that because water and roots, other elements reacting with it, have leeched what it allready had bound? in wich Ti and Ba would be a part., the good thing with real/notmadefromfossilized biochar is that i has a huge surface area, thats not “filled” where as the mined stuff has sucked everything it could from its surroundings and the water percipitating down.

    The amounts of heavymetals/harmfull substances present in horse manure and other, is very dependent on what medication the horses are getting, and what theyve been fed, everything is radioactive and contains some toxins, but that doesnt mean everything is as bad as coal ;) but brown coal dust is not as bad as i feared either, heres to hoping yours are low in the “bad” elements.

    Oh and why would you have me look in the ash residue of charcoal,, im probably missing something but i was looking for what could be measured from a lump of charcoal, like i did with the brown coal dust. except for carbon ofc :)

    regarding nathans, yes it would be a valid reason, but so would hes as other options are available yet more time consuming and labourous. i only reacted because; “So in your design you are using only manual labor, no fossil fuels etc.?” didnt feel rethorical, but thats the problem communicating via text.

    Oh and thanks for the correspondance, ive actually learned a great deal.

    1. We’ll be doing a soil analysis in the spring. I can check the garden soil foil heavy metals.

      CEC is the amount of cations certain soil or soil amendments can hold. It’s the amount of “places” certain soil amendments has for nutrients. It doesn’t indicate are thous “places” free or occupy. Charcoal and coal can increase they’re CEC as they are aged in the soil (or activated using chemical processing) as they’re surface area is increased.

      How much of those “places” are “occupy” is called base saturation. You can find quiet good explanation of both terms here:

      I also enjoy a good discussion, and I learn a few thing too!


  15. Hello! I just have a very basic question please: when you’re referring to ‘charcoal’, can I use a bag of charcoal that’s sold for barbecuing (provided of course that it doesn’t contain the additives for ‘easy lighting’? Thanks for any info! (Btw, I grew up in Germany, and my grandparents and parents used to spread the ashes from our wood burning stoves in their vegetable gardens :) )

  16. Hello
    I was just wondering if you could use rubbish e.g. plastic bottles food wrapers plastic bags ect or do you have to use organic materials. For people who live in tropical countrys without a rubbish collection system. This could be both a way to improve fertilaty and deal with the polution caused buy biuld up of exess litter in these regions. The region i am refuring to has verry sandy soils and is in the tropics and receives high yearly rainfall so biochar would be perfect i am just worried however if the plastics will be toxic to the soil

    1. Hi benjamin,
      I wouldn’t use plastic bottles or food wrappers as a source of organic matter to make biochar as you are probably going to end up with pieces of melted plastic.

      Also if rubbish are being burn in low temperature in low oxygen environment (that’s how charcoal is being made) some very harsh chemical compounds are being created.

  17. Stumbled across your website and comments and am fascinated. I live in western Virginia – and we have an abundance of black, bituminous coal available from the counties just to the west of us in West Virginia. I had never heard of or seen brown coal before as all of our coal here is high quality bituminous or anthracite. I usually get some bituminous each year to burn in my fireplace grate and have a pile of coal dust left each spring. Can I use that to make biochar? Also what about using the coal ash? I am always trying to learn more about organic gardening and farming and enrichment of the soil with use of chemicals.

  18. What a bummer – try to be sustainable and ‘green’ and one ends up supporting the fossil fuel industry. Is there no other way?

  19. Hurricane Katrina downed 90% of the trees in the forest we live in, leaving us with so much debris that we didn’t know what to do with. We decided to take all the debris around the house and bury it. 3 or 4 years later we forgot about the buried debris and set up a fire pit right on top. During our first fire we started seeing smoke seeping out of the ground all around us and in some cases 20 ft from another spot. Our ground was smoldering so we called the fire department and they came and dumped a 1000 gallons of water to put it out. A couples years later we decided to build our giant garden there because it was the only spot that got sunlight. Then……we learned about permaculture and that we had accidentally created a hugel bed infused with bio char and just happened to put our garden on top. haha!

  20. Add sand to clay
    throw money away.
    Add clay to sand
    money in hand.
    . . . . . –Great-grandpa’s adage

    1. Chris, that link is another piece of evidence that this ecological system we call earth is in very serious trouble. The o2 depletion is from land clearing primarily, and exacerbated by the plants/crops that follow. I think that the Amazon and Indonesia areas are taking us to that tipping point….added with big ag and the practices employed.
      Biochar used locally from local deadfall and mixed with local composts and such, is the only way the process is beneficial and sustainable. It cannot be used as a cure-all for the greater problems…..and dropping living trees for feedstock should be considered a crime against humanity.

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