All About Alfalfa

All About Alfalfa

When looking for good-quality alfalfa, be sure it's clean with no dust or mold--just as you would with any hay.

Photo: iStock

How much do you really know about this leafy green legume?

In some areas of the country, alfalfa is a regular part of life. It’s readily available and commonly fed, so it’s a logical foundation for many horses’ diets. In other areas, alfalfa is a delicacy of sorts, shipped in from different regions and bought a bale at a time on a vet’s recommendation to help certain horses that need nutritional support. For some types of horses—in either of those areas—-alfalfa simply isn’t a great choice. And, so, that fragrant green bale comes loaded with nutrients and, for some horse owners, a multitude of misconceptions. 

Whatever your alfalfa experience, we’re here to tell you everything you need to know about this forage, starting with a little bit of history, and clear up any confusion about it.

Alfalfa Goes Way Back

Forage for horses can be divided into two categories—grasses and legumes. Grasses you’re likely familiar with include orchardgrass, timothy, and bermudagrass and are long and stemmy. Forage legumes, such as clover and alfalfa, are members of the pea family and, so, are cousins of peanuts and garbanzo beans. 

“Alfalfa is a perennial legume, grown in most regions of the U.S. for horses and other livestock,” says Krishona Martinson, PhD, associate professor and equine extension specialist in the University of Minnesota’s Department of Animal Science, in Falcon Heights. 

Alfalfa was one of the first domesticated forages, planted and harvested in what is now Iraq, Iran, and Afghanistan several thousand years ago. Early farmers discovered its nutritional benefits, especially for hard-working horses, says Ray Smith, PhD, forage extension -specialist at the University of Kentucky (UK), in Lexington. “The main feed for horses of early armies in those regions was alfalfa,” he says.

“When alfalfa was first brought to the eastern part of the U.S. in the 1700s from Europe, it didn’t survive well—partly because of wetter soils and lower pH,” says Smith.  

By contrast, when settlers brought alfalfa west in the 1800s during the California Gold Rush to grow livestock feed, it did quite well. “Use of alfalfa grew rapidly in the western U.S. as people realized it fit well with that climate” and less-acidic soil types, says Smith. “By the late 1800s and early 1900s we began to learn more about adding lime to low-pH soils, to make them more appropriate for growing alfalfa. Plant breeding was also beginning by the 1900s, and plant scientists were able to develop alfalfa plants that were better adapted to various soils in the U.S.” Modern plant breeding has also improved alfalfa’s disease resistance.

Today, alfalfa still grows best in well-drained soils rather than wet soils.

Which Horses Benefit From Alfalfa? And Which Horses Should Not Eat Alfalfa? Continue reading this article in the April 2017 issue of The Horse: Your Guide To Equine Health Care. Subscribe now and get an immediate download of this issue.

About the Author

Heather Smith Thomas

Heather Smith Thomas ranches with her husband near Salmon, Idaho, raising cattle and a few horses. She has a B.A. in English and history from University of Puget Sound (1966). She has raised and trained horses for 50 years, and has been writing freelance articles and books nearly that long, publishing 20 books and more than 9,000 articles for horse and livestock publications. Some of her books include Understanding Equine Hoof Care, The Horse Conformation Handbook, Care and Management of Horses, Storey's Guide to Raising Horses and Storey's Guide to Training Horses. Besides having her own blog,, she writes a biweekly blog at that comes out on Tuesdays.

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