Botanic Notables: Kentucky Bluegrass

Botanic Notables: Kentucky Bluegrass

September 22, 2011
Photo by: Opha, Flickr

Welcome to Kentucky, where the grass is always ... bluer? It is known as The Bluegrass State, a nickname that evokes rhythms of banjos, fiddles, and mandolins. The style of string-band music has its roots in Kentucky, but why is it called bluegrass, and why are the state's fields green?

Botanically speaking, bluegrass (Poa pratensis) is a perennial species of Old World meadow grass, introduced to the United States by early European colonists. It thrives in temperate regions, and has become a popular grass for pastures and grazing fields (Poa is Greek for fodder). Poa pratensis has become a standard lawn grass in much of North America, but its first enthusiasts were Kentucky farmers, who found that bluegrass thrived in their limestone soil and was a particularly good grazing crop for their horses. 

Ironically, this means that the grass rarely grows to its full height of three feet, or the growth required for the grass to blossom with its blue flowers. Aside from these blueish seed heads, bluegrass resembles most other grasses: that is to say, green. And so the blue effect is seldom seen. 

Kentucky officially hitched itself to the grass in the mid nineteenth century, when it was popular for states to assume nicknames. It wasn't until the mid-1940s that the bluegrass style of music would share the name, when musician Bill Monroe formed a group called the Blue Grass Boys, after his home state of Kentucky, where the grass grows green, and flowers, blue. 


A specimen plate from 'English Botany Or Coloured Figures Of British Plants,' edited by John Boswell, c. 1902

Anna Laurent is a writer and producer of educational botanical media. Photographs from her forthcoming field guide to Los Angeles are available for exhibition and purchase at the author's shop.