Thanks for your post.
You can find more info on Terra preta here;
http://groups.google.com/group/alt.t...c5695c39ea5d7c
and here:
http://www.bbc.co.uk/science/horizon...eldorado.shtml.
I bought some horticultural charchol added it to my orchid mix (which the pack recommends). However it was expensive so I bought some BBQ charchol cheaper, but still dearer than I think it should be. ( It comes from Malaysia- from their rainforests?)I note in the article I mentioned in my previous post; that the charchol used in Terra preta soils was very fine, ground up, with few bits over1/2inch so, I have been bashing the BBQ charcol with a brick and it breaks up rather well. I have been adding this to my potting mix; then giving it a liquid fertiliser.
There may be a biological component to Terra preta soils. It may contain some unique microorganisms; reseach is away at Cornell Uni on this now.
I thought I would add a little sugar to the mix to see if this encouraged bacterial growth. Probably not a great idea but I have a couple of "control" pots and will see what happens.
I found a company called "Barmac" that sells activated charchol that is very fine and can be sprayed on turf. They have been selling it for years to professional greenkeepers and say it helps seed germination and will soak up a pesticide spill. That is their major sales pitch. I am not sure what the difference is between "activated" charchol and charchol.Do you?
I note bio-dynamic gardeners use a soil innoculant that they make from cow manure; burried in a cow horn for some months then mixed with water and sprinkled on the soil. I wonder if they are adding important microflora to the soil? There would certainly be lots of bacteria in the long, involved digestive processes of a cow.
I also know that professional Rose growers swear that cow manure is the ONLY fertiliser to use for good rose growth.
I have also been researching "horticultural clay". The Terra preta soils were full of pottery shards. Horticultural clay seems to be used mainly in hydroponic systems. It does have a fine porous structure and might provide a good home for bacteria or it might trap fertiliser. I think it could be some sort of catalyst to the whole tera preta dynamic.
Just a few thoughts.
I hope you find this topic as facinating as I do. You must try to see the BBC, TV show on this; it is a facinating archeological detective story.
Hope your plants grow well !
Michael
