Atmoscat, that is a great question and I'm glad you asked it. I promote the "windowbox" solution a lot, because it is easy to grasp, easy to implement, less expensive, doesn't smother the building with vegetation (and a lot of trimming work), looks goods, etc., and people get it. However, it is NOT the only pat solution. Hedges can work (but have potential disadvantages I just mentioned) and framing with shrubs can work (exactly as you describe ... shrubs at the ends/corners with lower plants -- often a groundcover below windows. The latter works well when windows are very low to the ground. One must make the call based on the particular circumstances.
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