Plant garlic around the base of the tree in the fall. This does not have to be any special type of garlic--any grocery store variety will work fine. Separate the cloves within the head of garlic and dig 6-inch holes around the base of the peach tree about 8 to 10 inches out. Place the cloves of garlic in holes right side up and cover firmly. Allow the garlic to grow in the spring, and it will keep borers from attacking the peaches and will prevent leaf curl.
Incorporate tansy plants into the areas under the peach trees to help prevent moths, flies, and ants. The common tansy grows wildly in almost all of the U.S., and farmers actually consider it a noxious weed in areas where cattle and livestock might ingest the toxic plant. It will start growing in April and continue flowering until September. It provides a pretty accent to the base of the peach tree with its yellow, daisy-like flowers.
Set some strawberry plants in the sunlight between your peach trees to attract the moths that might otherwise settle into your peach tree and then lay eggs in the peaches. The strawberries need lots of sunshine and plenty of mulch and they will grow vigorously near your trees.
Pop in some nasturtiums around the base of your peach trees. Its pungent odor is a general all-purpose bug repellent and although it will not last through the winter, you can use it as a pretty garnish for your salads. Again, it will add a nice color to your garden.
Cultivate some pungent herbs in and around your fruit trees. Choose ones like chives, tarragon, cilantro, dill and yarrow. Their smell alone will deter bugs and the blossoms will encourage the beneficial wasps and bees to inhabit your yard around the peach trees.