QuestionI found some copper sulphate in a shed. How much water should I use per ounce of copper sulphate? It depends in what form and at what content of copper, as to how to dilute it. What you will buy in a garden centre is labelled copper mixture and is a white powder. If you source it as bluestone which has a different strength then the recommended mixture is 50 grammes of copper sulphate mixed with 60 grammes washing soda and five litres of water.

Source: Irish Examiner June 13, 2021 08:00 UTC