In article .com,
"Martin Brown" writes:
|
| The main worry with coal and smokeless fuels is from trace impurities
| of heavy metals and boron that are concentrated in the ash waste.

Yes.

| Boron can be damaging to some plants (and weeds) and the heavy metals
| are perhaps not ideal use on your veg patch. Most plants will grow OK
| in soil with relatively high concentrations of heavy metals without
| much problem.

Only in fairly large quantities. It is an important nutrient in
small ones. Just like many other metals for both plants and animals!

I don't know how mobile it is in the soil.


Regards,
Nick Maclaren.