I will arise and go now, and go to Innisfree,
And a small cabin build there, of clay and wattles made;
Nine bean-rows will I have there, a hive for the honey-bee,
And live alone in the bee-loud glade.

Why did Yeats choose nine bean rows? Can’t say I know for sure, but let’s give it a try….
So let’s say that any number below five would not be enough bean rows for W.B.’s bean needs, then how about ” five”:

Five bean-rows will I have there, a hive for the honey-bee,
And live alone in the bee-loud glade.

It works, the “five” rhymes with “hive” and half –rhymes with “live”, but to my ear, there are too many “v’s”.

So let’s discard “six” because of that “x” and “seven” because of the two syllables and “eight” because it doesn’t chime with any of the other words, except maybe the “t” picks up the “t” in “there”. How about “ten”?

Ten bean-rows will I have there, a hive for the honey-bee,
And live alone in the bee-loud glade

We’re getting there: “ TeN, beaN, hoNey, aloNe,…….that “N” sound repeating but …..

”NINE ” wins !!! It has the consonance of the “n’s” and it also has that half rhyme with “hive” and “live”.

It’s almost as if Yeats knew what he was doing.

Footnote: A friend of mine told me recently that he had no recollection of studying Yeats at school. When he said this, those  opening line from The Lake Isle of Inisfree, sprang in to my head “I will arise and go now, and go to Inisfree”, which I have heard  so often that it has now taken on an orotund, stage Irish plumminess.

Our  English teacher, Mr Courtney, loved that “bee-loud glade”.