Shrubs that block out noise; ah, now there is a great wish! Just imagine if every time the wannabe rock band next door cranked up the decibels, all you would have to do is relax, knowing your 10-foot-high row of red-tip photinia would keep you cool, calm, collected and noise-pollution-free. Or you could rest in peace knowing that the guy across the street chainsawing limbs at 6 a.m. would not bother your snoozing at all due to the eardrum protection provided by your purple sage hedgerow. But, alas and unfortunately, neither sound nor plants work that way.
Having plants like ivy covering exterior walls helps a bit in reducing noise, as well as enhancing the walls appearance, giving it a classic look. The thicker the layer of vegetaion, the more the noise buffering effect. But, landscapers agree, plants do not really do enough.
Although thicker leaved plants like hollies muffle sound waves better than a dense-needled evergreen, that is not saying too much. Experts say that you would need to have at least a 100-foot-wide perimeter area of dense planting to see any appreciable reduction of noise level.
If only such plants existed. Shrubs that block out noise would outsell all other plants by millions! Growers would be hard-pressed to keep such horticultural wonders in stock. A black market would surely come into being with perhaps organized crime involved! Fear not, however. The prospects look slim that plant-and-tree crime lords will ever become a major social problem.
Because of the way sounds works and the way plants grow, shrubs that block out noise remain in the realms of the imagination. Unfortunately there are no plants that, when planted by themselves, contain the ability to soundproof our yards and/or our homes.
Berms, Not Plants, are the Answer
Sound barriers do exist, however. Typically engineered from stone, earth, or a combination of the two, sound barriers have been built with the ability to reduce sound up to nine decibels. This is a significant help when people living near a freeway, an airport, or adjacent to someone that blasts the neighbors periodically with highway hot-rodding suffer from increased deafness, rising blood-pressure levels, and the threat of cardiac arrhythmia. A decrease of nine decibels equals a 90 percent reduction in the troublesome sound! That could be lifesaving! But these miracles do not occur from shrubs that block out noise.
Although there are no shrubs that block out noise, people can add to the aesthetics of sound barriers by using plants. Providing it has been cleared through City Hall (or whatever your towns governing body is), shrubs can be planted atop the noise-reducing berm that makes up a legitimate working noise barrier.
Now, although planting shrubs does not eliminate noise, it has been proven that mass does helps deaden sounds. So if you have planted a very thick-growing shrub row, perhaps something like yaupon or arborvitae, you may add a little to the existing noise barriers ability to help drown out the racket.
Thick Fences and Thick Plants Worth a Try
Additionally, even though we know shrubs that block out noise have not been invented yet, they might help a little in other situations, as well. If your neighbors bass setting on his stereo causes your glass-paned windows (as well as your nervous system) to tremble and shake, you might want to consider building a fence made from very dense wood AND planting some type of thick-growing shrub against it. Who knows if it will work even measurably, but at least you are making the attempt, and if all else fails, you will at least have a nicely landscaped yard.
When All Else Fails
No, Virginia, we are sorry to have to say: Like Santa Claus, shrubs that block out noise just do not exist. But in the meantime, have you considered earmuffs, earplugs, or calling the police?
Landscaping for Privacy