As quoted by a Hungarian associate.
I am doing it different way than others. What is important is to start doing the prevention in the previous year. I give them systemic fungicide in autumn before leaf fall. It prevents infection through the leaves and buds. I also give them a copper washing in early spring. After leaf bud burst I give contact fungicide (cuproxat or/and Tiuram) every 7-10 days. I combine treatment with systemic contact once the leaves get bigger than 1-1,5cm. When it starts flowering it needs contact too. I also protect it from leaf curl twice after flowering. It must be good enough and it gives 99.9% success.
systemic fungicide – Systhane
copper washing – Copper Oxychloride or similar.
cuproxat – Active Ingredient (copper sulfate 27.1%)
Tiuram – 80% thiram (TMTD or Tetrametiltiuramdisolfuro)