Succulents are very popular, almost trendy, today. They are used both as indoor and outdoor plants and are pleasing because they are low maintenance, easy to grow, and hardy. One dramatic and stunning specimen plant for the outdoor landscape is yucca, specifically Adam’s Needle yucca (Yucca filimentosa). This beauty is hardy to zone 4 and will add a vibrant flair to your southeastern Wisconsin garden.
This Wisconsin native is in the agave family and was important to the Native Americans. They used nearly every part of the plant for a variety of purposes including food, medicine, cordage, and soap. The root contains saponin and was boiled and pounded to be used as soap. Roots were also beaten and pounded into a salve or poultice to be used to treat skin sores and sprains. Flowers were eaten raw and cooked; an infusion of the plant was used to treat various diseases.
The leaves of the plant contain long, extremely strong fibers (a type of sisal), the strongest fibers native to North America. The leaves were split into long strips that were plied into cording. The cord was used for binding, and to construct baskets, fishing nets, fishing lines and clothing.
To add to the desirability of this plant, they are deer and rabbit resistant, yet they attract bees and butterflies. They do not have any serious disease or insect problems. The one caveat, however, is their sharp spines. This would not be an appropriate choice for playgrounds or locations where small children might encounter them.
Adam’s Needle yucca is a cactus looking, multi-stemmed, evergreen, deciduous shrub. It has a semi-round form and very coarse leaves with tiny thread-like filaments along the edges, making it look like the leaves are peeling. The “Adam’s needle” part of the name comes from the needle-sharp points on the ends of the leaves. The plant will grow 3—4 feet tall and wide. In the late spring a striking flower stalk will rise up to 5 feet from the center of the plant. Nodding, bell-shaped, lightly fragrant, two-inch, white flowers will cover the stalk. Once the flowers have dropped, the stalk should be removed. Other than flower stalk removal, the only other maintenance necessary is to remove any old or winter-burned leaves in early spring.
Yucca will grow best in a full sun, dry location. They are tolerant of drought, sandy soil, and salt spray. This makes them an ideal plant for locations surrounded by high heat and light, such as parking lots or driveways and sidewalks. Once they are established, they require very little water. In fact, they will suffer from root rot if they are exposed to continually wet soil.
The thick rhizome roots allow the plants to survive in many soil conditions. They also allow the plant to spread by sending off small crowns or offshoots. The plant can be propagated by dividing these offshoots from the parent plant. Place the plants about three feet apart and water well the first year. Make sure of your site selection since as the roots grow larger, they also grow deeper and eventual removal will be difficult if not impossible. In addition, although this plant grows slowly, it will densely naturalize an area if left unchecked.
Carol Shirk, Certified Master Gardener