Question
I want to plant a thick flowering hedge to reduce noise from the road that runs east and west, about 30 feet to the south of my house.

I currently have a six foot wooden fence along the road. There are a few straggly bull pines (around 35 ft tall) inside the fence that I want to take out to provide more light for the house and hedge.

1. Will taking out the upper story of greenery provided by the trees substantially add to the road noise?

2. What should I plant for a hedge? Would a 2-3 ft high berm help with noise reduction? I want something drought tolerant. Purple or blue flowers would be ideal, but will consider anything. I'm in coastal northern California.

Answer
RB,

1.  Taking out these trees will allow more noise to get through, but I believe it should not be substantial.

2.  The berm will help to deflect the sounds up so it is a good idea.  Now the idea of a flowering hedge has plusee and minuses.  Usually a shrub that puts on a flowering show tends to be deciduous meaing losing leaves in the winter.  Doing so would you would lose any sound reduction.  You should plant a hedge composed of several species, both deciduous and evergreen.  

I can give some suggestions, but there are problems with this.  Since I have not seen your property I have can not make suggestions that would be appropriate for your particular situation.  My suggestion is to go to your local nursery and give them the criteria you want and have presented here.  They can show you what species they have available that meet your needs as opposed to me suggesting plants that you may not be able to get.

Good gardening

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