Peach trees have a yellow-gold to the leaves. What do they need?
Peach Leaves Turning Color
Certified GKH Gardening Expert
It is either a watering issue or a nutrient issue. Make sure the tree is getting water daily, twice a day in temps over 85 F. And give it slow release (balanced) fertilizer that will continually feed it. This article should also help: https://www.gardeningknowhow.com/edible/fruits/peach/fertilizing-peach-trees.htm