what in the world am i talking about? well, it is a gardening technique that is at least 3,000 years old. it's so old that it's new. new to us, but a common practice to the ancient amazonian tribes who grew corn, cassava and various tree fruits in superior soil that they enriched with compost, mulch and the newly termed 'biochar'. still lost?well, let's break it down:
bio- (bī′ō, -ə): life, of living things, biological
char (c̸här): to reduce to charcoal by burning, to burn slightly; scorch
so, with that said, biochar is basically organic matter that is burned slowly, with restricted oxygen flow, and then the fire is halted when the plant matter reaches the charcoal stage. yup, it is charcoal. naturally made from organic matter in the area around your garden. it is dried weeds, woody brush, and limbs that when turned to charcoal and incorporated into your growing space, can help hold plant nutrients, including nitrogen, phosphorous, calcium and magnesium. not to mention the presence of beneficial fungi and bacteria that thrive in high carbon soil. now, you get it? it isn't rocket science, even though scientists around the world are intrigued, but it is a simple and enviro option to improve soil, decrease waste and reduce the loss of nutrients. now, you do need to start with good soil in order for this concept to work. it isn't the answer to poor soil, but it is one way to help your soil retain what it has. so, hopefully you've been working on adding in the good stuff. if not, it isn't too late to start and biochar can help.
if you are nervous about the idea of starting fires in your garden, don't be. we aren't talking bonfire size, but rather small trenches with controlled burning. not a biggie. heck, we live in a small beach town and i was bubbling with excitement at the idea of making biochar when i first read about it. oh, you bet i was out there the first nice day foraging all of our dried up yard waste and wood scraps. it was wonderful! in no time at all i had a beautiful collection of biochar of my own.
so, put aside your smokey the bear 'don't start forest fires' mentality and go for it. oh, you don't quite have all of the details? this is what 'mother earth news' had to say about getting down to business:
"to make biochar right in your garden, start by digging a trench in a bed. then pile brush into the trench and light it. you want to have a fire that starts out hot, but is quickly slowed down by reducing the oxygen supply. 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 vapor. 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 smolder. then, after the organic matter has smoldered into charcoal chunks, use water to put out the fire."
there you have it. you aren't just limited to making biochar in your garden, but you can also collect charcoals from your fire place and camp fires.
i bet that you'll never look at charcoals, i mean 'biochar' the same. you'll be eyeing up those poor forgotten coals at the bottom of your fireplace and wondering, "where could i use them?" yup, you'll be hooked. all while adopting a practice that is over 3,000 years old, reducing loss of carbon into the atmosphere and improving your growing space. not bad!
have fun with it, research it for yourself and most importantly, BE SAFE!
