If you live next to a busy street, you may be able to reduce the traffic noise with your garden. Keep in mind that some sound experts aren’t proponents of using planting materials to reduce noise. They believe that noise barriers made of masonry, concrete, and wood work better. But what if you do have such a noise barrier but still can’t relax in your backyard? Many experts do agree that trees have the potential to help reduce noise by up to 8 decibels. If you’re like me, you may do anything for any amount of decibel reduction of traffic noise.
The best strategy is to plant a row of tall evergreen trees and then a row of evergreen shrubs. According to Raymond Berendt et al. in Quieting: A Practical Guide to Noise Control, a “single layer of trees is worthless as a noise barrier. Due to inter-reflection, multi-rows of trees are more effective”. They recommend thick rows of evergreen trees with smaller evergreen shrubs and plantings underneath. Also be aware of the height of the trees. In Landscape Architectural Graphic Standards, Leonard Hopper writes that you can reduce the noise level by 1.5 decibels with each additional 3 feet of tree height.
Some sound and gardening experts feel that trees and shrubs provide more of a psychological feeling of noise reduction. Again, if you’re like me and have a lot of traffic noise, you may be okay with your mind tricking you into feeling like your backyard is quieter—especially if you consider the additional benefits. Rows of trees, shrubs, and flowers not only reduce noise and provide a beautiful backyard; they also help block wind, provide shade, and absorb traffic pollution.
Some good plant choices for noise reduction:*
- Leyland Cypress
- Chinese Juniper
- Rocky Mountain Juniper
- Eastern Red Cedar
- Southern Magnolia
- Southern Magnolia
- Eastern White Pine
- Cherry Laurel
- Eastern Arborvitae
*Be sure to check which of these plants will work in your area.
By Shannon Mendez