I have been having a battle with leaf curl since buying a new peach tree about four years ago. When I asked for advice from the nursery I bought it from they said dont worry just remove curled leaves and it will come right in summer. as nearly all leaves needed removing it was quite a task the tree didn,t come right 2 thirds of the tree died back and every year it just gets smaller and any fruit that sets falls off when immature. I have just come across this advice which I am trying this year.
Don't remove the leaves, it is a waste of time, and it doesn't help the tree at all if you do it. Use your time to do other things instead like the ones that follow:
1. In early summer when it is getting hot, and no more rains, apply loads of fertilizers, especially high in Nitrogen. And supplement with Epsom salts. Supply adequate irrigation. The idea here is to help your tree recover vigorously to replace the infected leaves which will fall off. The biggest mistake of homegrowers is not to fertilize their trees when they have PLC infections. The new vigorous leaves will not be infected in the drier months, and it will help your tree prepare much better for next year.
2. Let the infected leaves fall, but promptly remove all the fallen leaves at most weekly, and burn them
3. In autumn, always remove the fallen leaves before they decay.
4. Apply your first batch of PLC fungicide in autumn. Spray also the soil and nearby trees, fences etc.
5.Mid winter around solstice, be sure to remove any leaves still hanging on the trees remove also any mummified fruit. Then spray with the strongest fungicide that you have, like lime sulfur.
6.early spring, when the buds are starting to swell, apply the last batch of PLC fungicide.
7. If you happen to have brown rot and twig blight, it might be good to spray diluted concentrations of copper on your blooms when it is rainy during the bloom time.