Several days back I wrote a post about me carrying vegetable waste—peels, juice waste etc. to my farm spreading them around and letting them decompose. Since last week I added coconut shells to the list. Using one coconut a week at home for garnishing poha, upma and idli chatni we end up using around 10 coconut a month. Imagine using 10 shells multiplied by 12 which come to 120 a year. In fact, its 240 shells (as the coconut is broken into two pieces) going to the municipal dump! From now onwards it will be less 240 shells. That will be my contribution in recycling and conservation.
I don’t litter them in my farm leaving them to the elements but process them to make biochar (or biocharcoal).
It is essentially charcoal, but burnt at a lower temperature and with a more restricted flow of oxygen. Remember the black thing (charcoal) used by the neighbourhood istriwala to heat up the iron to iron the clothes. Nowadays, he uses electricity to power the iron.
Biochar works in several ways. Though it is not filled with nutrients itself, it is able to attract and hold on to nutrients, so preventing them from leaching away, and holding them just where plants can reach them. Its porous nature provides refuges for mycorrhizal fungi, which in effect enlarge the plant’s root system while also increasing its resistance to diseases. It makes soil far more attractive and stable for beneficial microbial activity. Essentially it does everything organic matter does to the soil, but better, and permanently.
Dr Saran Sohi, of the UK Biochar Research Centre, started his career researching soils and soil additives. He says the effect biochar has on soil is different from that of any other additive.
“Biochar brings a physical and permanent change to the soil. Every other additive decomposes but biochar remains, and its effects increase over time,” he told The Telegraph.
How to Make Biochar
• Dig a deep trench in a bed. Use a fork to loosen the soil in the bottom of the trench and you’ll get the added benefits of this “double-digging” technique.
• Pile brush into the trench and light it. Fire starts out hot, but is quickly slows down as oxygen supply is reduced.
• The best way to tell what’s going on in a biochar fire is to watch the smoke. The white smoke, produced early on, is mostly water vapour. As the smoke turns yellow, resins and sugars in the material are being burned.
• When the smoke thins and turns grayish blue, dampen down the fire by covering it with about an inch of soil to reduce the air supply, and leave it to smoulder.
• After the organic matter has smouldered into charcoal chunks, use water to put out the fire. Another option would be to make charcoal from wood scraps in metal barrels.
Also check out biochar.info