By Linda235
Renfrewshire,
United Kingdom 
Has anyone used activated charcoal? It is supposed to be a good insecticide and fertilizer especially on roses and peas.
24 Apr, 2010
Activated charcoal is carbon with lots and lots of tiny holes in it (caused by burning out the impurities in the wood). These holes then attract and hang onto existing nutrients in the soil so I think you should regard it as a conditioner rather than fertilizer. No idea why its an insecticide though some people put soot on their plants.
24 Apr, 2010