The first treatment of apple trees should be carried out in early spring, before the buds begin to swell. During this period, it is crucial to combat the pathogens of various diseases. To do this, spray the trees with a 3% solution of Bordeaux liquid.
If you treated your garden with this substance in the fall, opt for a 3% solution of iron vitriol in the spring instead, as alternating these treatments is important for maximum effectiveness.
The next round of protection against fungal diseases should be applied at the "pink bud" stage. To avoid damaging the delicate young leaves, use a 1% solution of copper sulfate. Alternatively, other suitable preparations can be used for this purpose.