Dave2000
Deeply Rooted
I think caution is a good idea when thinking of applying copper to the soil. The toxicity issues mentioned in RidgeRunner's article should be heeded.
I worked in a greenhouse where some of the houses had been built and in use for over 50 years. That amounts to 365 day production in each of those 50+ years. The owners contracted with a soil and plant tissue test service and the guy showed up each month. One report was that the copper levels had reached toxic levels in one of the greenhouses and the soil should be replaced!
The owners got a bit of a start from this - enough so that they managed to discuss it around the employees. Swapping out the soil was dismissed but the idea was that copper based fungicides had been the problem. Wow! Enough to overload the soil?! Yeah, I guess so - a lot was sprayed on those roses growing in there!
Steve
What I don't understand is, if the test service was testing every month, why did they wait until the copper levels were that excessive before they said anything about it? Did they just send out incompetent techs then finally one that knew what he or she was doing? I guess it could have instead been a recent event where someone went way overboard putting on fungicide, new greenhouse employee or something.