Eco Friendly Gardening Techniques

[mikhurram]

Improving the soil structure

It is often said that “Feed the soil not the plant”. Everything associated with the plant: its health, the nutrients and pests attacking it are ultimately linked to the soil structure. Grasshoppers are unlikely to come near the crops if there is enough copper in the soil that is picked up the plants. Pests are mostly attracted to the scent of phosphate given by diseased or stressed plants. Use of pesticides over utilizes the phosphates which worsen insects’ attacks in the long run.. These predators wage a constant war on plants, and if farmers do nothing the output is likely to decline every year. This is why new seed more resistant to diseases are needed all the time. There are limits to relying heavily on fertilizers as in the case of China. Since 1990 Chinese grain production has been roughly stable but the use of fertiliser—which is heavily subsidised— has risen by about 40%.

A classic case is the depletion of soil by soil erosion in Haiti. Rice makes up 20% of the typical Haitian diet. In 1981 Haiti used to import 18,000 tons of rice. Now it imports 400,000 tons of rice. Main reason for the depletion of soil has been shrinking forests and the increasing use of fertilizer which have damaged the top soil structure. Less than 4% of Haiti’s forests remain. In contrast merely 2.2% of the area in Pakistan is inhabited by forests. Some say, as a nation’s soil goes, so goes the nation.

In the one of the episodes from Monty Don’s ‘Around the World in 80 Garden’ he travels to an Amazon rain forest of Brazil and finds a Red Indian woman burning charcoal and mixing it in the soil. Turns out that she is simply practicing what her ancestors used to do in the prehistoric age by making rich black soil.

The Amazon forest (Amazonia) contains some of the richest and most fertile packets of ‘Terra Preta’ soil (Black Indian earth). This rare earth soil is supposedly man made since it was found only in pre historic human settlements of South America. This soil was first discovered in ancient archaeological ruins where this terra preta soil, blacker than the blackest coffee, extended from the surface down as much as six feet. Top to bottom this soil was filled with broken pottery. The usage of these broken pieces of pottery in this the soil is akin to adding perlite or sand to potting mix, as a way of improving drainage and keeping the soil from baking completely tight under the sun.

Terra preta soil is characterized by the presence of low-temperature charcoal in high concentrations; of high quantities of broken pieces of pottery; of organic matter such as plant residues, animal feces, fish and animal bones and other material; and rich in vital minerals such as phosphorus, calcium, zinc, and manganese found rarely in most of the tropical soils. It’s most notable ingredient is charcoal – vast sources of it, the source of terra preta’s colour.

Unlike ordinary tropical soil found in Brazil, terra preta remains fertile even after centuries of exposure to sun and rain. The richness of this remarkable soil has been tested in the agricultural research centres of Brazil “Embrapa” where scientists test new crop varieties and tried to ruin or damage this soil by exposing it to sun & rain and till date have yet to succeed in destroying the richness of this soil

The key ingredient to terra preta is charcoal, made by burning plants and refuse at low temperatures. Results indicate charcoal rich terra preta contain 10-20 times more carbon than typical tropical soils and the carbons can be buried much deeper down. Reportedly by simply adding crumbled charcoal and condensed smoke to depleted soils tend to cause an exponential increase in the microorganisms in the soil which are vital for fertility. Charcoal seems to provide habitat for microbes-making a kind of artificial soil within the soil- partly because nutrients bind to the charcoal rather than being washed away. Tests results indicate that terra preta soil had a far greater number and variety of micro-organisms than typical tropical soils.

Apart from enriching the soil it is believed this black soil may help to combat global warming. Heavily plowed in our typical soil normally releases carbon dioxide as it exposes once buried organic matter. Some argue that creating terra preta around the world would use so much carbon rich charcoal that it could more than offset the release of soil carbon into the atmosphere. Some have even asserted that the mankind’s use of fossil fuels worldwide could be offset by storing carbon in terra preta nova. Residues from commercial forests, fallow farm fields and annual crops can be used to convert to charcoal.

However it has not been identified that how much carbon can be stored in the soil as studies indicate that there may be a limit in addition to identifying the microorganisms associated with terra preta.

Moral of the story is that we have focus on improving the soil structure by relaying on environment friendly sustainable technqiues and limiting the use of chemical pesticides/fertlizers. The next subpost in this thread would be based on ‘No Dig Gardening’ an eco friendly soil practice which apart from increasing the fertility of the soil helps in conserving water.

Note:
Most of the information was excerpted from
No Easy Fix, Economist Feb 24th, 2011
http://www.economist.com/node/18200678

The Future rests on soil. Can we protect it? National Geographic September 2008
http://ngm.nationalgeographic.com/2008/ ... /mann-text

Haiti’s degraded land can’t produce enough food, National Geographic September 2008
http://ngm.nationalgeographic.com/2008/ ... ourne-text

[newton]

Improving the soil structure

Terra preta soil is characterized by the presence of low-temperature charcoal in high concentrations; of high quantities of broken pieces of pottery; of organic matter such as plant residues, animal feces, fish and animal bones and other material; and rich in vital minerals such as phosphorus, calcium, zinc, and manganese found rarely in most of the tropical soils. It’s most notable ingredient is charcoal – vast sources of it, the source of terra preta’s colour.

Unlike ordinary tropical soil found in Brazil, terra preta remains fertile even after centuries of exposure to sun and rain. The richness of this remarkable soil has been tested in the agricultural research centres of Brazil “Embrapa” where scientists test new crop varieties and tried to ruin or damage this soil by exposing it to sun & rain and till date have yet to succeed in destroying the richness of this soil

However it has not been identified that how much carbon can be stored in the soil as studies indicate that there may be a limit in addition to identifying the microorganisms associated with terra preta.

There is significant evidence that this cultivation technique was in ancient times very popular across the agricultural regions of present day Pakistan. Thank you very much for putting a name to the technique. I thought it was unique to the Punjab/Baluchistan provinces but it seems to have been in use across the ancient worlds.

[Syed Adnan]

Charcoal or Biochar .. iam using it regularly in my pots at the top soil, it helps reducing soil diseases by trapping beneficial organisms , providing them a home to live in .

[mikhurram]

by Syed Adnan » November 12th, 2013, 9:40 pm

Charcoal or Biochar .. iam using it regularly in my pots at the top soil, it helps reducing soil diseases by trapping beneficial organisms , providing them a home to live in .

Kindly share with us the composition of your Biochar mixture and how are you preparing it? It may prove to be useful for others including myself interested in experimenting with biochar.

Secondly have you ever felt the need to fertlize this mixture or its rich enough (in terms of vital minerals) in your opinion to sustain the plants without resorting to fertlization?

[Syed Adnan]

I normally crush the charcoal and add a handful of it in the top soil,moreover in fish aquarium shop porous charcoal for carbon filters are available serving the same purpose, i add cornmeal (serve as food for beneficial fungus) in the soil also.
i dont think BIOCHAR has any fertilization property.

BIOCHAR + VINEGAR + CORNMEAL + COMPOST + MANURE + SAND = Pure Organic Gardening
This treatment is costly and i give it to bulbs and exotics only.

Peatmoss some how failed me and i believe it should not be used if somebody has fungus problem in soil.
This year i have started experimenting Solarization technique and addition of Trichorderma fungus into potting soil.

Following are some of the examples of the problem i faced in the past.

[M Farooq]

I normally crush the charcoal and add a handful of it in the top soil,moreover in fish aquarium shop porous charcoal for carbon filters are available serving the same purpose, i add cornmeal (serve as food for beneficial fungus) in the soil also.
i dont think BIOCHAR has any fertilization property.

BIOCHAR + VINEGAR + CORNMEAL + COMPOST + MANURE + SAND = Pure Organic Gardening
This treatment is costly and i give it to bulbs and exotics only.

Peatmoss some how failed me and i believe it should not be used if somebody has fungus problem in soil.
This year i have started experimenting Solarization technique and addition of Trichorderma fungus into potting soil.

Following are some of the examples of the problem i faced in the past.

That is an interesting mixture. What is the origin of this mixture? I mean did you read about it somewhere? I am guessing biochar must be alkaline and rich in potassium, because what we are left with after burning wood and plant material is pot-ash ( potassium carbonate i.e. the early origin of the name potassium). Does this explain why you add vinegar?

As to the sada bahar, its poor health is certainly due to poor drainage of the potting medium. Sada bahar does not tolerate over-watering and/ poor drainage. Would you like to share what is solarization technique for us?

Regards.

[mikhurram]

by M Farooq » November 13th, 2013, 12:16 pm
That is an interesting mixture. What is the origin of this mixture? I mean did you read about it somewhere? I am guessing biochar must be alkaline and rich in potassium, because what we are left with after burning wood and plant material is pot-ash ( potassium carbonate i.e. the early origin of the name potassium). Does this explain why you add vinegar?

As to the sada bahar, its poor health is certainly due to poor drainage of the potting medium. Sada bahar does not tolerate over-watering and/ poor drainage. Would you like to share what is solarization technique for us?

Dr Farooq,
You are more knowledeable than us and can guide us in the quest to identifying the suitable % of burnt coal content to used. I have some questions. You are right that biochar would be more alkaline in nature. This would imply that the sulphur content found in Amazon coal being burned along with plant debris by the ancient Aztecs must be having low sulphur content as the mixture is more alkaline? The key would be indentifying the % of coal ash to be added in the burnt plant debris, clay pieces etc. The most notable ingredient of terra preta soil is charcoal – vast sources of it and reportedly contain 10-20 more carbon than typical tropical soils.

Coal here in Pakistan has high sulphur content which if burned along with the plant debris would make the soil compartively more acidic which may suit us here in Pakistan as the soil normally is more alkaline is nature. In Brazil the soil ph is opposite to that of Pakistan i.e. more acidic in nature. In my opinion Vingegar is being used to the mix more acidic and may not be necessary as the sulphur content in our indigenous coal is quite high to make the soil more acidic.

In your opinion can we use the coal ash residue used in coal based Boilers that tend to burn coal at high temperature and mix it with other plant debris & other soil particles? According to the article the terra preta coal was burned at low temperature. I would be interested in hearing your opinion.

[M Farooq]

by M Farooq » November 13th, 2013, 12:16 pm
That is an interesting mixture. What is the origin of this mixture? I mean did you read about it somewhere? I am guessing biochar must be alkaline and rich in potassium, because what we are left with after burning wood and plant material is pot-ash ( potassium carbonate i.e. the early origin of the name potassium). Does this explain why you add vinegar?

Dr Farooq,
i have a question. You are right that biochar would be more alkaline in nature. It seems that the sulphur content found in Amazon coal being burned along with plant debris by the ancient Aztecs must be having low sulphur content.

Coal here in Pakistan has hight sulphur content which if burned along with the plant debris would make the soil compartively more acidic which may suit us here in Pakistan as the soil normally is more alkaline is nature. In Brazil the soil ph is opposite to that of Pakistan i.e. more acidic in nature.

In my opinion Vingegar is being used to the mix more acidic and may not be necessary as the sulphur content in our indigenous coal is quite high to make the soil more acidic.

If modern biochar is man-made, by heating plant material in the absence of oxygen, then it will have a high mineral content because the mineral cannot be distilled off. I am not sure if they ever wash the product before selling it or it is just raw charred plant material.

As to other question of burning sulfur rich natural coal with plant material is certainly more complex. Elemental sulfur itself is neutral, water insoluble material. However as you rightly pointed out that once sulfur is burned it will form acidic gases which may react with the highly alkaline plant ash to form neutral sulfates. But we really need to have a high sulfur content to neutralize all the alkaline plant ash. Someone must have analyzed biochar content and pH for sure.

Unfortunately, raw coal from Earth (not our wood coal) or biocharred products contain human carcinogens e.g. coal tar used for making our roads has plenty of cancer causing products. Historically, the first case of cancer from chemicals was discovered when coal tar was applied on rabbit ears. Poor rabbit eventually developed tumours just by skin contact of coal tar.

[mikhurram]

Thank you for the input. The terra preta soil mixture certainly appears to be complex. In one of the episodes of "Around the World in 80 Gardens" an Aztec woman is simply burning coal and mixing it with ordinary tropical soil. The clip lasts barely for a minute. I guess in all probability the coal being burnt must be 'wood coal'. Wood coal is available in Pakistan and it would be interesting to see how much it of it should be added in our common soil which is generally more alkaline. I intend to conduct an expriment by mixing slight portions of burnt raw coal residue along with burnt wood coal in leaf mold compost.

[M Farooq]

Thank you for the input. The terra preta soil mixture certainly appears to be complex. In one of the episodes of "Around the World in 80 Gardens" an Aztec woman is simply burning coal and mixing it with ordinary tropical soil. The clip lasts barely for a minute. I guess in all probability the coal being burnt must be 'wood coal'. Wood coal is available in Pakistan and it would be interesting to see how much it of it should be added in our common soil which is generally more alkaline. I intend to conduct an expriment by mixing slight portions of burnt raw coal residue along with burnt wood coal in leaf mold compost.

Wood coal would be safer to begin with. Lets see the outcome of your trial. Certainly the soil would become potassium rich. I vaguely recall reading that just simple wood ash was also used by ancient humans as a fertilizer. Good luck!