Best Plant Varieties for Windbreaks and Shelterbelts
Windbreaks and shelterbelts came into being during the Dust Bowl in the United States. They were first implemented in rural areas to stop the wind from blowing all the soil away. However, windbreaks and shelter belts are also useful for urban areas.
What Is a Windbreak/Shelterbelt?
A windbreak is a linear planting of trees and/or shrubs to lift the wind up and over a field or homestead. A shelterbelt is a grid of trees planted around a field to protect the soil and crops from the wind. I will use windbreak because a shelterbelt is a specific type of windbreak.
Benefits of Windbreaks
Windbreaks do more than just break the wind. When properly designed and cared for, they also control blowing and drifting snow. The snow stops in the windbreak and waters the trees and shrubs that make it up. More melt water is absorbed by the soil around a wind break, as well. Wildlife will use the windbreak to nest in and seek protection from winter storms. By cutting the wind all year and providing shade in the summer, windbreaks can save energy and heating and cooling costs. Finally, a windbreak serves as a living privacy screen.
Planning a Rural Windbreak
A windbreak in a rural area has more room to spread out than a windbreak in an urban area. In rural areas, a windbreak needs to be planted on two sides of the homestead to present a wedge toward the prevailing wind. First, a row of dense shrubs are planted, then a row of small deciduous trees, then a row alternating evergreens and deciduous trees, then a row of evergreen trees, and finally, a row of deciduous trees. If the windbreak faces south, east, or west, the inner tree needs to be shade tolerant or taller than the other trees. Otherwise, it won’t get enough sun to thrive. The space between rows should be twenty feet for a total thickness of 100 feet for the whole windscreen.
The spacing within rows varies. Shrubs and perennials in the outside row should be spaced 3-6 feet apart. Small trees should be 10-15 feet apart. Larger trees should be12-20 feet apart. Finally, the evergreen trees should be 20-25 feet apart in the row.
A windbreak for a field under cultivation is similar to a windbreak around the homestead. While it may seem that using 100 feet of arable land for a windbreak is a waste, crops have been shown to produce more when there is a windbreak to protect them.
Planning an Urban Windbreak
Most urban lots do not have enough space for a thick windbreak. However, a smaller windbreak with a dense shrub, a moderate sized deciduous tree, and an evergreen tree can be planted on two sides of a lot to protect the yard from wind and storms. The windbreak will help with energy costs and act as an oasis of habitat for wildlife in the area. Make sure any trees you plant will not get over 20 feet tall if they are under power lines.
Picking Plants
The most effective windbreaks have a mix of different species of perennials, shrubs, and trees. Planting a row of the same plant means that if a disease or pest were to come along, that whole row might be wiped out at once. For example, chestnuts were once planted along streets in a monoculture. When a disease came along that infected chestnut trees, they were killed and then cut down, leaving streets without any shade at all. By mixing species of plants, one disease or pest is unlikely to kill all of the plants at once.
The exact composition of your windbreak will depend on your client and the availability of water for supplemental watering during the time it takes the windbreak to establish and during droughts. There are many native plants that work well in windbreaks and are very drought tolerant once established.
As an example urban windbreak, consider the following plants. Of course, I would use multiple species for each row, but this is sufficient to illustrate the concept.
Black Haw Viburnum
Black haw viburnum is a shrub that grows 10-15 feet tall. It is native to the eastern United States. This would be one of the shrubs that would be in the outer band of the windbreak. It has big white clusters of flowers and is a hardy shrub.
Witch Hazel
A witch hazel tree would be my choice for the next row of my windbreak. Witch hazel grows in a wide variety of conditions and has a lot of winter interest. It grows 15-20 feet tall and that wide. The flowers are bright yellow and bloom in the fall and winter. They persist after the leaves of the tree fall off.
Sweet Bay Magnolia Tree
The sweet bay magnolia tree is native to the southeastern United States. It is a broad leaf evergreen tree with big, glossy green leaves and big, white flowers. Pollinators love the flowers. This magnolia species grows to 50 feet in most areas but can grow to be 100 feet if the conditions are right. The big white flowers are very fragrant. The red fruit is eaten by birds and small mammals. Magnolias are messy trees, dropping leaves all year long and dropping flower petals during the time it blooms, but they are such nice trees most people don’t mind cleaning up after them.
Care of Windbreaks
Trees and shrubs take three years to establish themselves in a new area. Using native plants means that after the plants are established, you will only have to water during a drought. The first year requires frequent watering while the roots start to grow. The rule of thumb is to water them every day for the first two weeks. Gradually expand the time between watering until you are watering the plants once a week. After the first year, gradually start watering less until you water the trees deeply every two to three weeks. The third year, water every 3-4 weeks. After that, gradually taper off watering and only water when during a drought.
We Can Help
Garden Plants Nursery has a wide variety of perennials, small trees, and large trees that will work for use in windbreaks. Call us at 931.692.7325 to get answers to your questions and to order plants.