Copper sulphate is sometimes recommended for canker. Any views?
1 Answers
Copper sulphate has the heavy metal copper and when present it can control fungi, but it does not give lasting control.
Canker is best avoided by not feeding with compost or farmyard manure and using only potash fertilizer, to harden the growth. Control grass and weeds for a two-metre diameter at least and reduce shelter so that trees dry more quickly.