Soil management is an integral part of farming. The soil properties continually need to be improved and factors upon which soil fertility depends need to be administered. Two types of components are used to adjust soil properties; fertilizers and soil conditioners.
Fertilizers are organic materials having a carbon-nitrogen ratio below 20:1. Those organic materials having carbon-nitrogen ratio from 20:1 to 30:1 can act as both; fertilizers and soil conditioner should be considered as fertilizers for the most part. The job of a fertilizer is to furnish plants with essential nutrients so as to contribute towards improved plant growth.
Soil conditioners are organic materials that have a carbon-nitrogen ratio above 30:1. Main purpose of soil conditioners is to improve soil quality making it more appropriate for plant growth.
One of the challenges (over-use of) agriculture fertilizers bring is nutrient rich runoff that begins to pollute surface water (lakes and streams for example) and ground water. Not only pollution, the leaching of the nutrients is a problem in itself for, rather being available to the plants, water along with useful nutrients, gets wasted. This, combined with other climatic issues like inconsistent rainfall and high night-time temperatures is creating serious challenges for farmers world-wide and coffee farmers in particular because coffee responds to climatic change so quickly.
Moreover climatic changes not only affect coffee plant growth and cherry production, they also pave the way for pests and diseases to prevail among coffee plants, enhancing damages that simply translate into further economic problems for the coffee growers.
Soil conditioners present good solution for a couple of problems that are interlinked in the above-mentioned scenario. First, soil conditioners enhance soil characteristics, decreasing leaching of the nutrients, making them available to the plants for longer period.
Second, soil conditioners minimize water evaporation from soil surface during hot weather. This in turn not only helps rain water retention in deeper soil layers but also help decrease soil temperature, something coffee plants are sensitive to.
Good news is, already economically challenged small holder farmers can obtain their soil conditioners cost effectively. All they need is a furnace or kiln. This too isn’t something they need to buy necessarily. A hole dug in the ground that is big enough and deep enough to burn dead, dried plant material will do too.
To obtain better quality final product “biochar”, an industrial thermometer is perhaps the only equipment farmer needs to buy. Industrial thermometer helps in temperature monitoring which helps ensure the production of better grade biochar. 400-700 oC is the optimal temperature to burn the waste organic material found easily on the farm like leaves and wood. Further this dead organic matter is mixed with something that can include nutrients into the mix; like compost. All this organic matter when burnt in a temperature and oxygen controlled setup (like a furnace or kiln) then leaves behind a solid char which is termed as biochar.
The bio-mass to bio-char ratio can be roughly considered as 4:1 that is; four tons of biomass gives off one ton biochar. Farmers can buy more controlled set up for this purpose if they want to that would cost from $5o-$500 and several top-lit updraft (TLUD) models are available in market.
Biochar in itself is not nutrient rich and so before mixing it with field soil, nutrients/minerals/fertilizers need to be mixed with it first. Its function and cost-effectiveness of its production is what makes biochar significant for the farmers.
We are living in an era where climate patterns are changing and where people are demanding to be more aware than ever about what they are ingesting and so any farming practice which is cheap in its implementation, natural in its method and has the potential to improve farm yield while fighting against harmful climatic impacts in any way cannot be undervalued.