Plant Highlight: Yucca schottii
Many of the Ruth Bancroft Garden’s Yucca species come into bloom in the spring, but Yucca schottii is summer-flowering. It does not flower for us every year, but when it does so it blooms in July and August. Like other species in the genus, it has bell-like waxy white flowers, and these are about 2 inches long (5 cm). The total height of the inflorescences on our specimen is about 4 feet (1.2 m), partly within the head of leaves but extending about 2½ feet (.75 m) beyond the leaf tips. At the bud stage, the flowers are tinged with purple, and this persists as a little purple tip on the outer 3 petals of the open flower, with a faint stripe of purple extending down the outside of the petal.
Y. schottii grows on both sides of the U.S. – Mexico border, in the states of Arizona and New Mexico on the U.S. side, and the states of Sonora and Chihuahua on the Mexican side. It is closely related to Y. madrensis, from farther south in Sonora, but Y. schottii is a larger plant with bluer leaves and larger inflorescences. Some botanists favor including Y. schottii within Y. madrensis, while others consider it a separate species.
Y. schottii can reach a height of as much as 20 feet (6 m), though more often plants are in the 10 to 15 foot range (3 to 4.5 m). It has sword-shaped blue-green leaves which are 1½ to 3 feet long (to just under a meter), somewhat stiff but still bendable. They have sharp tips and a very narrow dark brown margin, without the curling threads seen on the leaf margins of some other species of Yucca.
In gardens, Yucca schottii is very adaptable. It can be grown in shade, part sun or full sun, and can endure winter lows to as much as -10° F (-23° C). It should not be planted too close to a walkway to avoid having passersby get poked by its sharp leaf tips.