Welcome to the BigBiocharExperiment
This is the first large-scale experiment on the use of biochar in allotments and gardens. It aims to gather quantitative data on above- and below-ground productivity, and qualitative data on plant and soil health of widely used fruit and vegetable varieties. These data, combined with existing information on weather and soil quality, will be used to assess the effects of biochar on the productivity of plants across a range of soils.
Research on biochar is still in its infancy: we understand the long term benefits it has had on the Amazonian Terra Preta soils, however, long-term studies are only beginning. The Big Biochar Experiment aims to quantify the effects of biochar application. It is a joint effort led by researchers at Oxford University, Earthwatch and funded by Oxford Biochar. Thank you so much for all your help with peoplefund.it What is biochar?Biochar is a carbon-rich product, created by the slow burning of plant material with little or no oxygen. Biochar is organic, increases crop yields [3, 4, 5], improves fertilizer efficacy, breaks down pesticides, suppresses methane and nitrous oxide (two aggressive greenhouse gases) [6, 7] and sequesters carbon [8]. On a large scale, it is proposed as a method for reversing the carbon dioxide (CO2) build-up in the atmosphere, thus mitigating climate change.
Whereas inorganic fertilizers increase crop yields in the short term, their production is energy and carbon intensive. Breakdown of these fertilizers in soils releases nitrous oxide, a potent greenhouse gas. Globally, the production of fertilizers is the largest single source (38%) of emissions in the agricultural sector (EPA, 2010). Decreasing the use of inorganic fertilizers by enhancing the soil with biochar would therefore reduce GHG emissions even further beyond biochar's intrinsic ability to store carbon. 
Nikky's results on beetroots: yields were an astonishing 70.6% higher in the biochar plot. Neither biochar nor control plot were fertilized, in both cases, the seeds were grown on Growmore. 
Not all results are positive. Garlic thrives on acidic soils, this could explain why bulbs grown on biochar amended soils were smaller than those from the control plot. But we need more results to confirm this (we only have one data point so far), so if you are looking for a challenge, grab a few bulbs and get growing.
Insights from Pete Thompson, Tendring fruit: "As an onion farmer I noticed the stronger neck on the treated sample and that they are less bulby. If I saw a similar comparison of photos of spring onion samples I would guess that the treated sample had received more water because onions go bulby if they have less water – we require our product to be straight rather than having a bulb so we put on a lot more irrigation than those farmers who want a bulby spring onion. You can also see the difference at the ends of the rows where they have got less irrigation and have gone bulby if it is a dry summer. Hence it may be a sign of the ability of the char to hold soil water content at higher levels."    
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The wisdom of Ancient Amazonians Image: Jim Richardson
Scientists recently discovered that the ancient Amazonian tribes used to mix biochar in their soil. Thousands of years later, the soil they left behind (Terra Preta) still stands out as pockets of extremely fertile soils in the otherwise relatively infertile soils of the Amazon rainforest.
Preliminary resultsNOTE TO PARTICIPANTS: If you have completed your first year of the experiment, please stay with us. We would love to record the effects of biochar amendments on soil over a few years.
We're still collecting data and always welcoming new participants. Please continue sending your results in. Please go to our data collection page to send us your results. Please fill in your data sheet as soon as you can. We have begun the data analysis, but we could really do with more data. If your experiment was compromised by slugs, terrible summer, or laziness, please let us know. 
Nikky sent in remarkable results on radishes: yields were an astonishing 69.8% higher in the biochar plot. She also reported that the control plot radishes were "slightly 'hotter' to the taste". Would you be able to confirm this? If so, please mail us.
Results from River Cottage HQ. The biochar plot (top) showed a significant increase in sweet pepper yields compared to the control plot (bottom). More about this on the Environmental Change Institute website.
Our first large scale trial. Peter Thompson from Tendring Fruit is working with several collaborators to design a model orchard.
These pack choi seedlings were grown from seeds by Chris Goodall, Carbon commentary, Guardian Environment Network.
"I planted pak choi seeds in 20 small pots with your biochar (10% by weight) and New Horizon compost (...). It is probably not clear from the photographs but the difference to the naked eye is very substantial indeed. The germination rates was higher in the biochar pots compared to the control. The average size of the biochar seedlings is much greater. The biochar seedlings often had main roots 40 cm long, while the normal seedlings’ roots did not extend out of the pots.The leaf colour of the biochar seedlings looks much better. Overall, the difference is really striking and I will always plant in biochar enriched soil in the future." |
