Selecting a good location with full sun and good soil drainage are two of the most important aspects of planting a pecan tree. Before deciding on a spot for the tree, dig a hole 32 inches deep and 8 inches wide, and fill it with water. If it drains within eight to 24 hours, the location has good enough drainage for planting and if it doesn't drain, select another location.
Before planting a pecan tree, soak its roots for about an hour. While the roots are soaking, dig a hole for the tree that is big enough to fit the root ball and deep enough to cover just the roots of the tree. Place the tree in the hole, and firmly press the dirt down around it. When the hole is about three-fourths of the way full, add 5 gallons of water to it, and allow it to drain before filling in the rest of the hole. Avoid pressing down the soil on the surface around the tree once the hole is completely filled.
To ensure strong growth, stake the tree using three stakes and a rope to prevent damage for a few years. Water the tree often during the first several years after planting.