Pecan trees are large, growing 80 to 130 feet tall or higher with a canopy of leaves spreading 30 to 50 feed in all directions. They need plenty of space away from power lines, buildings and fences. The root system will be expansive, so plant away from sewer, gas and water lines. Pecan trees are capable of bearing nuts for hundreds of years, so it is worth the effort to find a suitable location. They prefer hot, humid summers and are hardy in USDA hardiness zones 5 to 9.
Select a grafted bare-root plant. Trees grown from nuts will not grow true to variety. Most nursery stock will contain a 1-year-old scion grafted onto a 3-year-old root stock. Choose a tree with a scion of 1/2 to 1 inch in diameter. Look for a strong taproot with many lateral roots branching from the taproot.
Plant bare-root trees in February, allowing time for the roots to establish before spring growth begins. Remove grass and weeds from the planting area and keep this area cleared to at least 3 feet of the tree trunk.
Dig a hole large enough to accommodate the root spread and deep enough for the taproot with extra room. In heavy soils, dig the hole at least 1 1/2 foot deeper than the taproot.
Mix organic compost or peat moss into the soil. Do not use commercial fertilizers or manure; these may burn the roots.
Transplant pecan trees as soon as possible after purchase. Soak the bare roots in a bucket of water for at least an hour before planting, longer if the roots appear to have dried out.
Plant the tree in the hole 1 to 2 inches deeper than it was previously grown. After the soil settles, the tree should be at the same depth that it was in the nursery.
Spread the roots out in the hole with the taproot stretched down. Fill in around the roots with soil. Fill the hole half full and water well to settle the soil. Continue backfilling with soil to within 6 inches of the surface and water again. Finish filling the hole, leaving a basin around the tree to catch water.
Prune the pecan tree after planting, removing 1/3 to 1/2 of the top of the tree, if this was not done at the nursery. Prune lateral branches to 6 inches.
Wrap the tree trunk loosely with burlap, aluminum foil or heavy paper to protect the tree from sunburn during the first year.
Water once a month until the first leaves appear, then increase watering to once a week. Water thoroughly so water reaches the full depth of the roots. Do not allow water to stand around the base of the tree for long periods.
Fertilize with 1/4 lb. of urea or other nitrogen fertilizer and 1/8 lb. of zinc chelates when the leaves appear.