We protect our avocado tree by using a white latex paint diluted with some water by painting the trunk and branches. Avocados burn easily and in addition to the paint, they also need to be shaded from the sun. You can buy a tarp that allow filtered light to come through or you can attempt to make your own as we have done. Also it is important to remind you that if you are dealing with clay soil you will need to amend the area where you are planting the tree. To amend clay soil use a combination of sand, compost, vermiculite, penlite, and potting soil. This will ensure that water will penetrate deep to the root ball. You can also take a pvc pipe with drilled holes and bury it alongside the tree when transplanted. Flood the pvc pipe with water to ensure the tree gets water from the ground up.