How Much Water Will a Weeping Willow Need?

The graceful, drooping branches of the weeping willow tree are often seen swaying over stream beds and along the banks of rivers and lakes. Hardy in U.S. Department of Agriculture Plant Hardiness Zones 2 through 9, the weeping willow has a rapid growth rate and reaches up to 70 feet in both height and width by maturity. This tree has a dense, round, weeping growth habit, grows best in full sun and needs plenty of water.

Weeping willow trees enjoy plenty of water.

Soil and Water Requirements

Weeping willows prefer moist, well-drained soil and wet loamy conditions. Able to withstand flood conditions, weeping willows also grow well in wetlands. Water regularly during dry periods to prevent the tree from losing its leaves; it will survive drought periods, but leaf-drop will be significant if the roots dry out. When planted in dryer conditions or away from a direct water source, if rainfall is limited, provide regular irrigation throughout the season. Adaptable to all pH soil conditions, this tree will perform well in both acidic and alkaline locations.

Planting and Care

When planting the weeping willow, consider its mature size and choose a location with room for its large spread and weeping features. The aggressive root system spans three times the distance from the tree canopy to the trunk, so do not plant it near sewer lines, septic systems or underground water sources because the roots could cause severe damage. The weeping willow is one of the first trees to develop leaves each spring, and with yellow fall color, one of the last to drop its leaves as winter approaches. Young trees require regular pruning and plenty of water to develop a strong mature tree structure.

Ongoing Watering Needs

Give the weeping willow a soak of at least 1 inch of water per week, increasing the watering frequency if experiencing a dry spell. If the area allows, add a 3-inch layer of mulch to young trees to help maintain the moist conditions the tree prefers.

Diseases and Watering

The bacterial disease crown gall affects weeping willow, causing round galls to form at a bud, graft joint or at the soil line. Early galls are tan colored, change to black with age, and vary in size from 1 inch up to 1 foot in diameter. Dig up and dispose of young infected plants, cleaning all garden tools well when complete; older trees will survive crown gall but will weaken due to the infection. Canker is a fungal disease that surrounds branches causing foliage to die off. Prune out the infected branches and provide the tree with added fertilization and water well; canker typically does not affect strong, healthy trees. Keeping the weeping willow well watered and the soil moist will help keep the tree healthy and able to fight off disease.