Yes, I need to know when is the best time to thin or trim peach tree branches that are laying too close to the ground.
Late winter or early spring is the best time to prune peach trees like this.
I have a peach tree, and some of the leaves turn yellow on the edges and the tips are brown. The tree is being watered twice a week. What could be the reason of this, and should I do something about it?
While it is watered twice a week, it may not be enough. make sure that you are watering 2" on the entire root system. Typically the root system will spread out at least as far as the canopy does.
If this is a tree that has been planted in the past year, than it will need significantly more water than an established tree.
Try increasing the water and also check the roots to make sure that the roots are healthy and that there is nothing preventing the roots from taking water up.
I only had a few peaches on my peach tree. Last year I pruned the trees back. I have 3 of them this year and they have not any peaches on them.
It is likely a pollination issue. These articles will help:
https://www.gardeningknowhow.com/garden-how-to/beneficial/insect-pollination-process.htm
https://www.gardeningknowhow.com/garden-how-to/beneficial/creating-a-pollinator-garden.htm
It may also be improper pruning. Make sure that you are properly pruning the tree. This article will help with that:
http://pubs.ext.vt.edu/422/422-020/422-020.html
Each one of my ripe peaches has one small white worm in them by the pit. How do I prevent this?
Sounds like a peach borer. Here is an article that you may find helpful: https://www.gardeningknowhow.com/edible/fruits/peach/peach-tree-borer.htm
Why do my peaches drop off tree before ripening? They are about the size of a large walnut. They are clean looking, no spots etc.
Peach trees tend to drop fruit when they either do not have enough water or enough nutrients. Make sure the tree is getting enough water and fertilize the tree.
My fiance transplanted a 9 foot peach tree. and this spring it had some sprigs of leaves and then it quit. However, it's still alive. Do I need to prune this tree to get it to flower and come back?
It's going through shock. This article will help: https://www.gardeningknowhow.com/plant-problems/environmental/learn-how-to-avoid-and-repair-transplant-shock-in-plants.htm
Some leaves on peach tree have yellowed. Fruit is now falling off. Some discoloration on branches. What could be the problem?
It sounds like a fungus of some kind. The most common is peach curl. This article will help you with peach curl, but most peach fungus are treated with the same methods as peach curl:
https://www.gardeningknowhow.com/edible/fruits/peach/peach-leaf-curl.htm