Willow trees are highly desirable to home landscapers for their graceful form, according to Ron Smith, a horticulturist for North Dakota State University. Unfortunately, warns Mr. Smith, willow trees are not very hardy trees. They need to be planted in the right location and can be plagued with a number of serious problems. Home gardeners who wish to grow a willow tree, whether it's a weeping, corkscrew or pussy willow, should know how to care for it properly if they want their tree to thrive.
Plant your willow tree in a location where it will receive a full day's worth of sunlight. Willow trees need at least six hours of sunlight, and preferably much more than that, in order to thrive.
Provide plenty of water for your willow tree. All willow trees, and especially weeping willows, need consistently moist soil to grow well. Water enough so that the soil is moist at all times.
Fertilize your willow each spring with a water-soluble, slow-release fertilizer designed for deciduous trees. Follow the directions on the package according to the size and age of your tree.
Monitor your willow tree carefully for signs of fungal diseases. Canker growth (dry, black, cracked areas of wood) can girdle branches, killing them. Prune away infected branches to stop the spread of the fungal disease. Treat the tree with a systematic fungicide each spring.
Spray your tree with insecticide to keep sucking insects from infesting the tree. Boring insects can be devastating to willows, and topical insecticides do not kill them, so if you see signs of boring insects (holes in the wood and sawdust piles) contact a tree professional to treat your willow.