Plant Profile: Yucca rigida (Blue Yucca)

Just planted

Latin name: Yucca rigida ("YOU-kah ri-GEE-dah")
Common name: Blue Yucca, Silver Leaf Yucca, Palmilla.
Originally from: the northern Mexican states of Chihuahua, Coahuila, Durango, and Zacateca.
Blooms: A tall spike of creamy-white flowers emerges from the central crown in spring.
Light: Full sun.
Water: Winter rain is enough.
Height x width: 15' x 5'
Zones: 7-10
Where to find in P. Garden: We have two at the top of at PG

This beautiful slow-growing tree-like yucca grows up to 15' tall, with occasional branching. The attractive 3 foot long by 1 inch wide, stiff, slightly waxy, pale silver to whitish gray leaves have narrow yellow margins and are dense, giving a symmetrical and architectural appearance.

Flowers in bud

The old leaves point downwards, creating a skirt on the stem, and finally fall off leaving a soft fibrous covering on the trunk. When it flowers, this species is as stunning as many other Yuccas.  In spring, huge clusters of white flowers hang off a thick 2' long spike that pops out from within the crowns.

Like other Yucca species, Y. rigida is pollinated by moths, and after being pollinated the flowers develop into short-cylindrical pods with pointed tips. After a couple of months, the capsules dry and split open to release the black seeds.  We don't have those moths locally, so sadly we won't be getting any seed pods.

This Yucca is like all the other hardcore drought tolerant members of it's family, performing best in warm sunny areas with good drainage and occasional to infrequent summer irrigation. It prefers alkaline conditions and is hardy to around 0°F.

Foliage pairings

We planted three of these in early 2019, and one died - it had been somewhat buried in mulch at the base, and I think that rotted it.  However, the remaining two look outstanding and are growing and flowering. Perhaps we will replace the first one with another - with a small trunk!

This Yucca is similar to Yucca rostrata, and the two are often confused. Y. rigida has leaves that are much more stiff - rigid, in fact. Y. rostrata has shorter, slightly twisted and softer leaves.  I have heard a joke about how to tell the difference between Yucca aloifolia and Yucca elephantipes, and it kind of applies to the difference between Y. rigida and Y. rostrata. If you fall into a patch of Y. elephantipes (or Y. rostrata) you will emerge pretty scratched up. If you fall into a patch of Y. aloifolia (or Y. rigida) you won't emerge...