Why Is Kentucky Called the Bluegrass State?

Kentucky’s official nickname is “the Bluegrass State” because of how prolific the type of grass known colloquially as “bluegrass” is throughout most of the state’s lands. Bluegrass is a specific type of grass belonging to the scientific genus Poa, and it gets its name from the bluish-purplish tint the stalks take on when they go to seed. A genre of music from the region also carries the name, and the northernmost region of the state, where the grass is perhaps most prolific, is commonly known as the “bluegrass region”; though significant, neither of these is the reasoning behind the nickname, though. Fields of waving blue in the distance are often a point of pride for residents, and the association has become tightly bound with the state generally. The legislature approved it as an “official” nickname in the 1960s, and since the late 1970s it’s been printed on most Kentucky license places and tourism materials as a matter of course.

Most states have a couple of different nicknames, some of which are more popular at certain points of history than others. Many of these are informal, but nicknames that are “official” — like Bluegrass State in Kentucky — usually carry a bit more weight. Most of the time they must be approved by the state’s legislature, often by way of a vote. The biggest difference between official and unofficial nicknames is how they’re used, mostly when it comes to marketing materials and information published formally by the state.

Different legislatures have different criteria when it comes to what makes a nickname worthy of approving, but in general they look for something that’s timeless and permanent, and is likely to hold relevance for a long time. In Kentucky, the choice of a natural phenomenon that holds a place in the imagination of most residents and is associated with the region broadly on a national and international scale seemed a likely choice.

Bluegrass is native to Europe and Asia, and came to the U.S. with some of the earliest settlers. It generally took well to the new soil, perhaps because of how hardy and weather-resistant it is. By most accounts it’s grown more today in Kentucky than in most other parts of the United States, but it wasn’t always this way; settlers brought it to the region from elsewhere, though it quickly took off.

This type of grass grows especially well in Kentucky's limestone soil, and the Bluegrass State's pastures feed many of the thoroughbred racehorses that are raised in the area. Some people are surprised to learn that blades of bluegrass are not actually blue, they're green like most other grasses. Its name comes from its purple-blue buds that provide fields of bluegrass with a bluish tint in the spring. When the grass is trimmed or mowed down and not allowed to go to seed, this effect may never be seen; as such, many people in the area may actually be growing bluegrass without even realizing it.

Bluegrass music is an acoustical genre that is derived from traditional Scottish, Irish and English music. In bluegrass bands, musicians playing instruments such as the guitar, banjo, fiddle, base and Appalachian dulcimer take turns improvising on the melody while the other musicians provide backing and rhythm. The commercial pioneer of this type of music was Bill Monroe, who hailed from the Bluegrass State. His band, known as Bill Monroe & His Blue Grass Boys, was popular for several decades starting in the 1930s. This style of music continues to be celebrated at annual festivals throughout Kentucky.

Kentucky is usually divided into five regions for geographical and agricultural purposes. The northernmost region is known as the Bluegrass Region, and it is further divided into two parts, called the Inner Bluegrass and the Outer Bluegrass. The Outer Bluegrass consists mainly of steep hills and is not conducive for horse farms. Hundreds of thoroughbred horse farms are located within the Inner Bluegrass, however, and the region is widely known within the horseracing community.