I have about 20 kg so maybe I will lookup more information and then run a trial to see what effect it has. I know the article I read said that there was an increase in leaf size and production. But I will need to check up on the ratios and also on that heavy metal. Thanks for the information so far.
I have now found some more information on the use of Fly ash in growing tomato. Ref Link
http://www.ncbi.nlm.nih.gov/pubmed/15091390
looks like it could be benificial but I think I will still do some test myself and see what comes of it.
Last thing I want are tomatoes which look great but can't be eaten as the are contaminated with heavy metals and other chemicals.
Would be nice to know if anyone has tried it before and what the outcome was.