[reg s]

Has anyone experience of using charcoal as a soil conditioner?I tend a school allotment in the East Midlands and the soil is heavy clay.I have available quite a bit of charcoal made from burning coppiced wood (mostly hazel and hawthorne)
Can the charcoal be used as a soil conditioner and if so at what `dosage` and when,does it need to be fine particles etc.I would be grateful for any `hands on` advice as there appears to b elittle or nothing published in the usual gardening books.
thanks, reg s

[mumofstig]

I've certainly only recently heard of it, so have no experience.
You probanly already know that there's nothing in modern books because although used in antiquity it has only recently been rediscovered.
Research is ongoing, with some trials going on.
http://www.bigbiocharexperiment.co.uk/

also worth a read?
http://www.motherearthnews.com/Organic-Gardening/Make-Biochar-To-Improve-Your-Soil.aspx#axzz2LzabwiEP

[SkyeEnt]

I'm also interested in charcoal as soil conditioner, although I don't have a source for it yet (although once my coppice trees get to the right size I hope to make my own  )  I gather it's very good for lighter soils acting as a reservoir for water and nutrients, so just what I need on Skye with light rainwashed soil!  I wonder whether you'll get the same effect on clay soil, since that tends to be quite good at it anyway?  It also helps the soil warm up due to the darkness I think, which may be your main effect & may help improve drainage, which may also help on clay.  You say it's a school allotment - is that just on a school, or run for educational purposes?  I think it would be great if you could do an experiment, one plot no soil improver, one plot charcoal (or more than one with different dosing regimes), and one plot with a standard soil improver, eg composted green waste.  You could grow the same crops in the plots and see whether you get a beneficial effect.