Seeds Batlle 730045bols Fungicide Copper, For 5 L

I have cedar-rust on my Bonsai apple trees. I tried many products and in the end I knew it had to copper in my fungicide. This product seems to help a lot, but it left blue spots all over the leaves of my Bonsai. I used a touch less of the powder to avoid blue residual marks, but I got them , I was very accurate on the measurements and mixed the solution very well and also as I was using it I kept up shaking my spray bottle.

good