Adam's needle

Perennial · Shrub

Yucca filamentosa

Adam's needle

Also known as: Yucca smalliana, Yucca concava

A tough, clump-forming stemless yucca with curly white threads on its leaf edges and tall spires of creamy bells.

  • Full sun
  • 0.5–1 m (2–3 ft)
  • 1–1.5 m (3–5 ft)
  • H5 · Zone 7
  • July–September
  • Evergreen

Overview

Native to the south-eastern United States, this Yucca forms low rosettes of stiff, grey-green, sword-shaped leaves with curling white threads peeling from their edges. In late summer, established plants send up tall spikes of nodding, creamy-white bells up to 2m high. In its homeland it is pollinated only by yucca moths, so seed pods rarely form elsewhere. It is one of the hardiest yuccas (about -15°C), tolerates more moisture than desert types and spreads slowly by offsets.

At a Glance

Sun Full sun
Height 0.5–1 m (2–3 ft)
Spread 1–1.5 m (3–5 ft)
Hardiness H5 · Zone 7
Flowers July–September
Soil Chalk, Loam, Sand
Moisture Moist well drained
Habit Clump forming, Rosette-forming
Water Low
Maintenance Easy

Growing Conditions

Min. Temperature -15°C (5°F)
pH Range 5.5–8
Fertility Average
Drainage Free Draining

Aspect Suitability

  • East-facing
  • South-facing
  • West-facing

Site Tolerance

  • Exposed sites
  • Wind
  • Coastal
  • Salt
  • Drought

Soil Tolerance

  • Chalk
  • Sandy
  • Loam
  • Acid
  • Neutral pH
  • Alkaline

Foliage

Yucca filamentosa (Adam's needle) foliage
Persistence Evergreen
Colour Grey-green, Blue-green
Leaf shape / texture sword_filamentous
  • Architectural foliage

Foliage interest: 12 months of the year

Seasonal Timeline

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Flowering
Foliage
Propagate
  • Flowering Jul Aug Sep
  • Foliage 12 months of the year
  • Propagate Mar Apr

Maintenance Calendar

  • Apr Pull or cut off dead outer leaves wearing gloves and eye protection, as the tips are needle-sharp
  • Apr Separate offsets with roots if clumps become crowded or you want more plants
  • Oct Cut faded flower spikes to the base, because the rosette that flowered slowly declines and offsets replace it

Garden Design

Works well in: Desert / Dry, Mediterranean, Modern / Contemporary, Prairie / Meadow, Tropical / Exotic

A reliable, cold-tolerant way to add spiky structure to a sunny gravel border, coastal garden or large pot.

Companion planting: Grasses, Sedums, Lavenders, Eryngiums

Wildlife Value

  • Moths
  • Other pollinators
  • Shelter

Safety

  • Toxic to dogs
  • Toxic to cats
  • Toxic to horses

Contains saponins, toxic to dogs, cats and horses if chewed. Leaf tips are very sharp - plant away from paths and children's play areas.