Corkscrew willow trees are one of the most beautiful and easy to care for trees you can add to your landscaping. They are similar to weeping willows but are named for the twisting habit of their branches and leaves. Willow trees prefer fertile, slightly acidic soil which drains well but holds moisture. They are fast-growing, hardy, and relatively care-free once they are established. They resist disease well and provide beauty and shade as they reach maturity. Insects can be a problem but are easily managed with common pesticides.
Plant your tree in the late summer six weeks before the first frost to give it time to establish itself. Dig a hole twice the depth and diameter of the root ball. Keep roots moist during the planting process and quickly fill in the hole after planting to avoid the roots drying out. Do not fertilize for the first month, and then only conservatively. Do not fertilize the tree directly, but add to the soil around the tree. Add mulch in a circle around the tree roughly the diameter of the branch spread to keep down weeds.
Maintain your tree's growth by keeping the soil moist, and in the spring after new leaves begin to sprout, fertilize lightly with a high-nitrogen fertilizer. Use a pruning saw to remove any dead branches. Seal any pruning wounds with wound sealer. Willows are prone to rot at the site of broken branches or cracks.
Watch for insects. A healthy tree will generally be its own best defense against insects, but if insects are a problem, treat with appropriate pesticides, which are available at any garden center. Willows may be attacked by aphids, gypsy moths, lace bugs, willow leaf beetles, and willow and poplar borers. All are manageable by pesticides, but none of these should seriously harm a healthy, established tree.
Watch for disease. Several common cankers and fungi attack willows, but none are usually serious enough to warrant control. Prune out infected branches when attacked by cankers or fungi. Powdery mildew, tar spot and rust are not usually serious enough to warrant control. Regular fertilization will keep most trees healthy enough to fight off disease on their own. Rake up and dispose of any infected leaves at the end of the season to avoid re-infection the following year.