This plant is also known as Great Plains Yucca, Dagger plant, and Spanish Bayonet.
Yuccas prefer dry, rocky areas and will spread extensively given the right growing conditions, roots can grow sideways as far as 30′. Be sure you like this plant before you plant it. Removal may be impossible once it is established. It is drought tolerant and prefers full sun. This yucca will reach about 2′ tall and about 3′ across when grown. The top photo is from 2007, the bottom from 2018. The plant receives afternoon sun from ~noon till sundown and no water except when it rains.
Flowers will be white or red on stalks like traditional yucca but closer to the ground. Flowering is late May through July. I find mine prefers to bloom in the fall and winter. Flowers close during the hottest part of the day and open at night to be pollinated by moths. I find bumblebees love this plant. It’s rare that I walk by and don’t see a bumblebee or two raiding the pollen.
The pollen is extremely heavy and sticky and is not carried by the wind but only by the moths. Female moths form balls of pollen which they take to other flowers and use to protect the egg they implant deep in the flower.
Yucca store water in the trunk of the plant. Some have flexible soft leaves, some have stiff leaves. Most all will form trunks with time. When trunks form, the dead leaves remain covering the stem. Leave the dead leaves in place, the shelter the stem from extreme heat and sun.
Many yuccas do not bloom every year. Many bloom after floods or rainy spells. If you’re having trouble getting one to bloom try giving it a really good soaking.
This yucca easily handled several hard freezes over several winters.
Soapweed yucca is a very slow growing plant, and unimpressive when not flowering.
Yuccas are better’n most succulents about being in beds with plants that require more water.
Roots form a soap like foam when wet. Yucca is the state flower of New Mexico.
No problem handing heat wave and drought summer 2011, it’s 2018 and it’s still here, slightly larger and flowers every summer.