Willow trees grow very quickly into magnificent shade trees with long sweeping branches. The scientific name is Salix babylonica. Willow trees thrive when planted near a water source. These trees grow best in USDA hardiness zones 6 to 8 and mature to heights ranging from 30 to 40 feet with 35-foot spreads. Training willow trees requires staking newly planted trees to provide proper support as it grows and pruning the tree as needed for better air circulation.
Place two stakes 12 inches from the planting hole on opposite sides of the willow tree. The length of the stakes depends on the size of the willow tree. Use stakes long enough to be buried 18 inches deep and extend up two-thirds of the total height of the tree.
Attach wires to the top of each stake. Use a piece of rubber hose on the other end of the wire to secure the wire to the willow trunk loosely. Wrap the hose around the tree and then attach it to the wire or place the wire inside the hose around the trunk. Never wrap the wire alone around the trunk, which could damage it. Check the tree often to make sure the supports remain loose enough for slight movement and do not cause any harm to the trunk. Remove the supports within a year of planting the willow tree.
Prune any broken, weak or diseased branches found on the willow tree at any time. Discard diseased branches after cutting to prevent spread of infections. Plan regular pruning of the willow tree during the dormant season.
Cut any branches on the willow tree touching the ground. Remove any branches crossing over or touching other branches. Look at the overall shape and prune the willow tree to create a natural balanced crown. Space the upper branches 2 inches apart and rub off any growth emerging on the trunk of the tree. Cut off any branches growing straight up on grafted trees (ones with large knots on the trunk), but do not cut upward growing branches on natural willow trees.