Yucca filamentosa, also known as Adam’s needle, is a trunkless flowering plant commonly associated with landscapes of the Southwestern United States.
Technically a broadleaf evergreen shrub, Yucca filamentosa is related to asparagus, succulents, and cacti as they are all members of the family Asparagaceae.
Yucca filamentosa 'Color Guard' photograph by K M.
Adam’s needle is known for its long growth time as it can take several years before flowers start to form.
Flower stalks typically start to pop up during late spring, resulting in a massive increase in the plant’s height, and blooming takes place soon after, during the summer.
Yucca filamentosa plants in bloom, photograph by Carl Lewis; CC.
The Yucca filamentosa plant is highly resistant to drought, diseases, and pests.
Growth doesn’t require too much overlooking. Usually, good plant care dictates that the flower stalks be removed every season along with any dead leaves, although it is not vital to plant health.
Yucca filamentosa can grow in pretty much any soil, although the soil must be properly drained to ensure there isn’t an oversaturation of water.
Fertilizer usually isn’t necessary, but in the event the plant appears to be struggling, adding some nutrients sometime during the spring might be a good idea.
Sun damage is rare and the yucca plant benefits considerably from access to sunlight, so having it directly out in the open is good for plant health.
However, a limited amount of shade won’t cause any long-term harm.
Adam’s needle is best adapted to warmer conditions, as heavy winters can cause issues.
To ensure the plant is well-protected during cold periods, covering it in mulch and limiting how much it is watered will go a long way in preventing damage.
Adam’s Needle growing in containers, photograph by James St. John; CC.
Wild-type Yucca filamentosa flower close-up, image by Maja Dumat?; CC.