Question: I would like some advice on fast-growing plants to block out a railway line at the bottom of our garden and, if possible, deaden the sound. Would bamboo be any good? Laurel and lavatera have been suggested, but laurel sounds a bit boring.
Answer: Choosing plants for screening is a question being asked increasingly to the RHS Gardening Advice team, as life outside our gardens encroaches. There are several good choices, but the sound deadening qualities are less easy to define. Evidence seems to be that plants are not especially good noise blockers. The thickness of the barrier is the main factor - the thicker the better. Consider going for broad-leaved evergreens for the best effect - cherry and Portuguese laurels, as you suggest, for example, and also conifers, such as Thuja plicata, are likely to be as good as any plants. Magnolia grandiflora, Quercus ilex - the holm oak - would also give you a sturdy screen and can be kept trimmed to the height and spread that you need. Eleagnus ebbingei, too, would do a good job and has beautiful scented, although tiny, flowers. If you don't mind the thread of runners, bamboo would work too.
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