The Heritage Herb Gardens at the Ozark Folk Center grace the park with visual colors and textures, sweet and pungent aromas. With their natural display, they help us to interpret the history of the human use of plants.

As a member of the Herb Society of America’s Ozark Unit, I am choosing vetiver grass as my signature plant for the year 2010. The signature plant program encourages research so that members of IHA can become expert on any herb they wish to know better. In this way unit programs are developed, members sharpen study and presentation skills and the goal of educating members and the public is achieved in a thorough and diverse way.

Vetiver grass, formally known as Vetiveria zizanioides was given the new genus name Chysopogon in 1991. Also known as khus khus, this herb is a tall, clumping grass that is native to tropical Asia. It is cultivated in Haiti, Réunion and Java for the essential oil of its roots. The essential oil is valued in the industries of perfumery and flavoring. I keep the essential oil of vetiver on hand for making insect-repellent oil for my skin.

The Heritage Herb Garden has had this easy-to-grow plant for at least two decades. We grow it in containers as it is not hardy here in zone 6b. According to Dr. Art Tucker and Tom DeBaggio in The Encyclopedia of Herbs—a Comprehensive Review of Herbs of Flavor and Fragrance, vetiver is only hardy in zone 9, marginally so in zone 8.

Clumps of vetiver will survive in one-gallon growing containers. Every year or so the roots are turned out of the pots, chopped off to about 3-inches long,  and divided into four new plants, using a sharp hatchet or big knife and pruning shears. The tops of the leaves are cut back to between 4 to 6-inches. The new vetiver plants are then transplanted into fresh potting medium and are good to grow on for another year or two.

The severed roots are the harvest. These must be washed and rinsed until free of dirt or growing medium. This is a pleasing, fragrant job. They are welcome in any room in my house. The aroma has been described as woodsy. After the moisture has left the roots they can be placed in muslin bags and stored in linen or cedar closets to help repel insects from linen and wool.

If vetiver grass is planted in the ground, the roots will plunge 10-feet straight down into the soil. They are very difficult to dig and harvest from our rocky garden beds. This characteristic is put to good use on loose, eroding soils in tropical climates. The roots hold soil in place, even on slopes, defending the land from mudslides and acting as a filtering system to catch and trap pollutants that are carried in runoff. Vetiver grass is being used to reclaim landfill property in China and to prevent mudslides in Southern California. Vetiver will adapt to wet or dry sites and will tolerate heavy metals in the soil. To top it all off, the plants of Chysopogon zizanioides are sterile and will not produce viable seed. They also retain a clumping form rather than producing stolons and become invasive. I only wish I could grow a whole field of it! If I don’t see you in the future—I’ll see you in the pasture.