By Bill Ward
Published in The Boerne Star in July 2005
Operation NICE! (Natives Instead of the Common Exotics!) plant of the month for July is twist-leaf yucca (Yucca rupicola). This native of the Edwards Plateau has been in the horticulture trade in the US and Europe for many years.
It is the flexible wavy leaves, some with a helical twist, that make this yucca an attractive landscape plant. The low-growing heads of twisty leaves have no visible stems. Leaves are from 8-24 inches long and less than two inches wide. They narrow toward the base and, on the other end, taper to a stout, sharp spine. For many people this “soft” yucca is a less-threatening landscape plant than the typical stiff-leafed varieties which are hazardous to brush against.
During late spring, twist-leaf yucca sends up a bloom stalk, usually a few feet high. The upper part of the stalk has numerous branchlets with blossoms of white or greenish-white drooping petals. Unfortunately, deer consider the bloom buds to be choice delicacies.
Twist-leaf yucca is a versatile landscape plant because it will grow in full sun or in the understory shade of large trees. Judging from where it occurs in nature, twist-leaf yucca also is very drought tolerant. This little yucca is common in Kendall County and over the whole southeastern Edwards Plateau. It also grows on the western part of the Edwards Plateau and in some parts of north Central Texas.
In the wild it can grow in thin rocky soils. Indeed, its species name rupicola suggests that twist-leaf yucca can be described as rupicoline, growing on or living among rocks. In my yard, these yuccas are one of the few things that thrive in the thin dry soil near roots of large liveoaks.
Jill Nokes (How to Grow Native Plants of Texas and the Southwest) recommends twist-leaf yucca as “very effective on difficult-to-landscape sites such as rocky slopes or escarpments, in shallow soils in groupings with bear grass (Nolina spp.), cedar sage (Salvia roemeriana), Turk’s cap (Malvaviscus arboreus), and fragrant mist flower (Eupatorium havanense).”
Certain plant experts have written that twist-leaf yuccas are difficult to transplant from the wild. Not having read this, a group of us included twist-leaf yuccas among the native plants we got permission to rescue at a future construction site. We dug up and potted two or three dozen small twist-leaf yuccas, and virtually every one of them survived to be a robust plant.
The Boerne Chapter of the Native Plant Society of Texas provides free planting and care instructions for twist-leaf yucca at Boerne nurseries participating in Operation NICE!: Hill Country African Violets and Nursery, Barkley’s Nursery Center, and Maldonado Landscape and Nursery.
Twist-leaf yucca is only one of at least 16 species of yucca native to Texas. Many of these adapt to home landscapes, and most provide annual stalks of white flowers. Sally Wasowski (Native Texas Plants) wrote, “I love their white waxy flowers at night, when they release fragrance to attract the white moths that pollinate them.”
The yuccas at night …. all smell just right …. (clap, clap, clap, clap) …..deep in the heart of Texas.
