We learned it young from Schoolhouse Rock. Those of us who studied Landscape Design were compelled to learn why, and assume that it is always true.
Well, I am not a landscape designer. I am just a horticulturist and arborist. I can see why three is the best number for groups of trees, and that five is probably the second best option for larger groups, followed by seven, and then nine, and so on. I sort of understand why two, four, six, eight and so on are not so desirable. However, these rules are not absolute.
When I was a kid, many suburban front yards were outfitted with three European white birch trees. Such groups were typically in a corner of the rectangular yards, just outside of the curvacious mowing strips that were designed to make the rectangular spaces seem to be more irregular than they really were. Individually, the…