I think it is quite widely used for sorting out powdery mildew, snails and slugs. Been reading this article to learn more about the compound.
" Copper sulfate is an inorganic compound that combines sulfur with copper. It can kill bacteria, algae, roots, plants, snails, and fungi. The toxicity of copper sulfate depends on the copper content.
You can be exposed if you are applying copper sulfate and you get it on your skin, breathe it in, or accidentally eat or drink a product. This can also happen if you get some on your hands and eat or smoke without washing your hands first. " Source
Seems like can it can cause alot of issues ( Eating large amounts of copper sulfate can lead to nausea, vomiting, and damage to body tissues, blood cells, the liver, and kidneys. With extreme exposures, shock and death can occur.) and possibly lead to kidney cancer with longterm over exposure to it.
Because its water soluble and if applied to plants in vegging stage of growth, it should not be present when harvest season comes as its leached into the soil.
Attached the pics of what I’m talking about , I’m from Europe so perhaps we have different agricultural system
I am in the frontier country where Europeans arrived as a buffer/farming zone for the nguni tribes coming south in Africa. This was 201 years ago, European settlers ( French, German, Dutch and English ) barely survived with the agricultural tools they brought. Although we still considered european, we have defiantly changed our farming methods.
" They were granted farms near the village of Bathurst, Eastern Cape and supplied equipment and food against their deposits, but their lack of agricultural experience led many of them to abandon agriculture and withdraw to Bathurst and other settlements like Grahamstown, East London and Port Elizabeth, where they typically reverted to their trades.
A group of the 1820 Settlers continued on to Natal, then a part of Zululand, home of the Zulu people. At the time, King Shaka ruled the territory with highly trained warriors. Leaders of the Natal settlers requested permission from Shaka to stay on the land." Source