Willows make a good, fast-growing screening option for homeowners. Willows will best help to screen an area from late spring through fall. For example, if your concern is in camouflaging a pool, willows should develop and retain their foliage throughout the summer months — the prime time your pool is in use. According to the Virginia Cooperative Extension, willows can not only block the view of undesirable objects, they can help cut down on noise pollution. Even though they lose their leaves in winter, the trunks and branches still offer some degree of protection and act as barriers against wind and snow.
Plant a grouping of willows 2 feet apart in a single or double row for a hedge, or try a weeping willow tree between the pool and the areas you hope to screen. You may need to plant more than one group of plants to block the view of an object from both your home and yard. Willows can survive in a range of soils and are drought-tolerant. Specimens can grow 3 to 11 feet in a season, depending on the variety, and require full sun.
Willows are a great choice for wet areas, but the University of Minnesota Extension cautions homeowners to take care when planting them near utility reservoirs of water. Any location containing household plumbing — including sewage and septic systems, water lines or well pipes — can become damaged as roots seek out sources of water underground.
Keep bare root willows wet until planting. Several can be quickly planted by inserting a shovel blade into the soil, pushing the soil to the side and slipping the roots between the back of the shovel blade and the side of the hole. Remove the shovel and allow the dirt to fall back into place. Water the newly planted willows daily.
Take cuttings from existing plants for a low-cost option. The University of Nevada Cooperative Extension recommends cutting willows for transplant when temperatures are below freezing as the plants will be in a dormant state. Choose 0.5-inch diameter or slightly larger branches.
Cut 1.5- to 2-foot-long sections of branches. Slice the lower ends of the branches at an angle and the top ends flat across. These cuts will make planting the willows easier. Snip off any growth until you are left with straight rods.
Pound the willows into the ground by striking the flat ends of the branches with the side of a hammer, driving the angled end into the soil until 60 to 90 percent of each rod is below ground. Perform this chore before the ground freezes or after the ground thaws to prevent the need to store the branches. This will also minimize any damage to the bark and make the job of inserting the branches easier.
To encourage a bushier form, Bluestem Nursery describes pollarding and coppicing, two severe methods of trimming that can encourage a thicker growth of branches. Coppicing involves cuts made near the ground, with only a thumb-sized piece of exposed trunk allowed to remain. Pollarding involves cuts made 2 to 3 feet high along the trunk for thicker branching starting at that height.
Add a row of lower-growing shrubs beneath the willows for greater screening if you need coverage down to ground level. Willow branches and foliage extend far down the trunk if not pruned back, but they tend to leave a gap up to 2 to 3 feet off the ground where the branches are sparse or nonexistent.
Plant willows for a quick screen, but follow up with a line of hardy trees nearby to take over if or when the willows begin to fail. According to the Iowa State University Extension, willows are susceptible to many diseases because of their rapid growth and can begin to die far sooner than slower-growing trees and shrubs. They are also prone to storm damage because of their delicate branches. Adding another line of trees will give you a secondary, backup barrier after the trees have time to mature.
Homeowners with allergy and hay fever issues should be aware that willow pollen can cause a reaction.
Virginia Cooperative Extension: Trees for Problem Landscape Sites-Screening
University of Nevada Cooperative Extension: Tips for Successfully Planting Willows in Riparian Areas
University of Kentucky Cooperative Extension: Willow
UK Forestry Commission: Establishment and Management of Short Rotation Coppice
Bluestem Nursery: Pruning Willows for Ornamental Effect
Colorado State University Cooperative Extension, Denver County: Creative Screening with Plants
Bluestem Nursery: Willows for Screening
Bluestem Nursery: Willow Growth Rates – Heights of Coppiced Plants
Gorge Commission: Recommended Plants for Screening
FAO Corporate Document Repository: Tree Pollen and Hay Fever
Iowa State University Extension: Fast-Growing Trees Die Young