Can I add a point to your excellent post. For many years i was a chemical gardener using lots of sprays, pellets etc. One year we had a bad batch of the fertilizer and instead of getting a large crop everything was killed in a matter of days. This was a bit of a wake up call for me and from that moment onwards I have not knowingly used any thing other than organic products on the vegetable patch. However for the first few years the crops where a lot smaller and not as healthy but that didn’t put me off as i figured that i must have been damaging the soil for years and that it would take some time to get back to normal. Today i am now getting better crops than when i was using chemicals and I feel healthier as well.