Create Your Own Paradise:
Improving the Soil with Terra Preta and Biochar
By Ute Scheub, Haiko Pieplow, Hans-Peter Schmidt, Kathleen Draper
When people try to imagine paradise, they usually think of a garden. We feel comfortable in gardens and recover from all kinds of stress. Gardens are places of richness, of fertility, and of plenty. We delight in them with all our senses – the warmth of the sun, the colors of butterflies, the shapes and scents of flowers, the smell of damp soil, the taste of fresh fruits, the sounds of rippling water and courting birds – or simply enjoy the peace and quiet. Maybe, now and then, a fat slug slithers through the idyll, and you imagine it chuckling to itself because it has just feasted on a fresh young lettuce that you had lovingly tended – something in paradise has to be annoying; otherwise, it would be boring.
Green is healthy and beneficial: people of all cultures and nationalities prefer a natural landscape to a concrete urban environment. Studies have shown that in hospitals a view of greenery from a patient’s window encourages the healing process and reduces the dosage of painkillers that would otherwise be required. Trials in Germany, Holland, and the USA have demonstrated that Nature in the direct vicinity has a positive effect on the contentment and health of those living and working there. Gardening is all the more healthy, as you are moving around in fresh air, light, and sun the whole day. And in the evening, you can reflect with satisfaction on your day’s work – if only it wasn’t for the pesky old slugs.
So it’s not surprising that not only in the countryside but also in cities gardening is increasingly in fashion. Young and old; women, men, and children; those with or without employment; natives and refugees work the land, form intercultural gardening associations, cultivate green plots behind their houses, or tend some piece of communal land. Some people also do it because they are fed up with the callous production of food and the perverted globalized power of the agro-industrial complex.
Our most important message is a hopeful one: climate gardeners using terra preta can reduce the greenhouse effects on the earth’s atmosphere. Climate farming – applied globally and supported by other environmental measures – could even reverse them. If we, by means of climate farming, were to raise the humus content of soil by ten percent within the next fifty years, the carbon dioxide concentrations in the atmosphere could potentially be reduced to preindustrial levels. Maybe, as the Australian professor in earth and life sciences Tim Flannery stated in his open letter on biochar, the use of biochar “represents a cornerstone of our future global sustainability.”
What is Terra Preta?
Terra preta, which simply means “black earth” in Portuguese, is also sometimes termed “miracle earth.” The latter is certainly an exaggeration; after all, it is just a man-made fertile soil and not a witch’s brew that you throw over your left shoulder at a full moon, spit on the ground, and say abracadabra, and the world is saved. Nevertheless, this ancient cultivation method used by the original inhabitants of the Amazon region has the potential, according to a growing community of international scientists, to tackle the global problems of hunger, poverty, water shortage, and climate change simultaneously. Which other methods can make such a claim?
According to current knowledge, the advantages of terra preta techniques are immensely diverse – they encourage fertile soil, healthy plants, and food; enable high and reliable yields within a small area; relieve smallholders and gardeners from dependence on expensive fertilizers, toxic pesticides, or genetic technology; transform waste products into natural manure; solve problems of hygiene in slums and sanitary systems; detox soils; transform steppes and poor soils into agricultural land; and decisively lessen the effects of climate change.
What is Biochar?
How? The key component of terra preta is biochar, charcoal made from organic residues and produced by means of climate-neutral pyrolysis, exposure to heat in a low-oxygen environment. If you pyrolyze organic wastes, up to fifty percent of the carbon, which plants have extracted from the atmosphere in the form of carbon dioxide, is converted into highly stable carbon, which can persist in soils for thousands of years. When introduced to the soil, biochar, which is rich in pores, serves as a fertile store of nutrients and water. How this actually happens is explained in our book, Terra Preta: How the World’s Most Fertile Soil Can Help Reverse Climate Change and Reduce World Hunger. Every hobby gardener and every smallholder can produce their own version of terra preta; if you have too little time, you can also order the necessary ingredients via the Internet.
However, the details of what these methods can and cannot achieve have by no means all been researched. A hurdle to its large-scale application in agriculture, at least for the time being, is cost-effective production of large amounts of biochar by modern pyrolysis facilities.
Conventional agricultural research institutes also show little willingness to finance and participate in appropriate research projects. This is hardly surprising, as there is the potential in black earth techniques to replace, or at least reduce, agrochemistry and genetic technology, the purveyors of which fund an increasing amount of research at agricultural universities. Similar to decentralized renewable energy, which in the long term threatens the existence of the central energy corporations, the increasing spread of terra preta methods would ultimately cut into the profits of agroindustrial players. We have to be prepared that at some stage, those promoting biochar will feel their opposition, which may take the form of excessively high safety regulations that the lobbyists of the agro-industries may promote to increase barriers to entry in the agricultural sector.
In all probability, we have passed not only “peak oil” — the point in time when the maximum rate of oil extraction has been reached and after which easily extractable oil amounts shrink and become increasingly expensive — but also “peak soil” — the time when the amount of non-toxified fertile land is decreasing and becoming ever more costly. Unlike climate issues, however, the soil has, up to now, no political lobby, though its global state and the impending climate catastrophe are closely linked.
As it is barely more than a decade since the rediscovery of this ancient horticultural technique, the practical horticultural experiences are unavoidably limited. There is still a huge amount of details to research, such as which kinds of vegetables prefer which kind of substrate and what are the ingredients of this substrate. The more gardeners gather and share their experiences, the quicker knowledge about terra preta will spread. Let yourself become infected by the terra preta bug and talk about your experiences and observations with your neighbors, or via social media, local journals, or the radio. You may also join the new Biochar Journal and exchange your newly gained knowledge with other climate gardeners and farmers.
How long the soil of our one and only planet remains fertile is in our hands. With terra preta and the knowledge of how best to use it in different scenarios, we can begin to create a modern garden paradise worldwide where we can live better than we do now: a paradise 2.0.
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Stockholm Biochar Project
The City of Stockholm, Sweden is in the process of investing in pyrolysis plants to produce both biochar and renewable energy from park and garden waste. The renewable energy will be turned into heat that can be added to a local or a district heating network. The biochar will be used within Stockholm in the public gardens. Some will also be given back to the citizens to be used in their private gardens and allotments.
In Stockholm, trees are planted in structured soils. Large rocks are compressed to create a stable structure, allowing the plant roots to spread even in environments with heavy traffic. A well allows storm water to enter the soil and gases to exit. The structured soils are made from local leftover construction materials, but the soil that is added is made from non-renewable materials such as peat, sand, and clay. Stockholm started searching for a material that they could produce from local resources to substitute the finite materials. They stumbled upon biochar, and ever since 2009, biochar has been used in the city’s plant beds. The improvement to the overall health of the trees has been remarkable.
Park and garden waste is collected from both the city and the residents in Stockholm, but it is difficult to dispose of. City managers and the energy company Fortum are focused on increasing renewable energy production. The combination of an interest in biochar, the difficulty in disposing of park and garden waste, and the goal of producing more renewable energy launched the Stockholm Biochar Project.
The vision of the Stockholm Biochar Project is to enable citizens and the city to tackle climate change while improving the local environment by producing biochar and renewable energy from park and garden waste. Using the biochar as a soil conditioner in public and private plant beds, the project will create a vast carbon sink that will help reduce overall greenhouse gas levels in the atmosphere.
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Facts About Terra Preta
Terra preta is a dark, fertile soil first made by the original inhabitants of the Amazon Basin at least 2,500 years ago.
Terra preta means “black earth” in Portuguese.
The key component of terra preta is biochar — charcoal made from organic wastes (wood chips, crop residue, food scraps, manure) exposed to heat in a low-oxygen environment.
Anyone can make terra preta on the smallest of garden plots, in urban or rural settings, private or communal gardens, window boxes or square-foot gardens.
Climate gardening (aka farming with terra preta and biochar) offers one of the few safe and proven technologies to help draw down carbon levels in the atmosphere.
Biochar added to soils can not only help improve food security by boosting yields, and increasing soil fertility by increasing its capacity to retain water and nutrients, but also can improve food safety by reducing pathogens such as e-Coli.
Not all types of biochar are the same. If buying biochar, it is best to buy certified biochar.
Using terra preta in both small and large scale agriculture can contribute to the meeting of the UN’s Sustainable Development Goal 2: End hunger, achieve food security and improved nutrition and promote sustainable agriculture.
Excerpted with permission from the publisher from the book Terra Preta: How the World’s Most Fertile Soil Can Help Reverse Climate Change and Reduce World Hunger, by Ute Scheub, Haiko Pieplow, Hans-Peter Schmidt, & Kathleen Draper. 2016. Published by Greystone Books in 2016.