Blue Witch

Blue Witch © GBarton

Blue Witch Nightshade
Solanum umbelliferum

Description (Jepson,

  • Eudicotyledon
    • Eudicots are a major lineage of flowering plants; see family for general characteristics
  • Nightshade Family (Solanaceae)
  • Evergreen to deciduous shrub
  • Stems green and densely hairy
  • Leaves oval and hairy
  • Flowers
    • Inflorescence (flower arrangement) is a loose cluster of blue-purple flowers at the top of stems
    • Each flower has 5 fused petals and sepals (usually green, outer flower parts)
      • Prominent, thick, yellow anthers (pollen-producing part of the stamen/male structure) surround the protruding pistil (female flower part)
      • Base of each petal has 2 green spots
    • Ovary superior (above the attachment of other flower parts)
  • Fruit is a berry (a usually multi-seeded fruit with a fleshy ovary wall), initially green, becoming purple when mature
  • Height to 2-3 ft.; may grow wider than its height


  • Native to California
    • Grows in chaparral and low-elevation oak woodlands
    • See Calflora for statewide observations of this plant
  • Outside California, grows in Arizona and south into Baja California, Mexico
  • Grows at elevations to 5,200 ft.

Uses (San Mateo County Parks prohibits removal of any natural material)

  • Fruit eaten by birds
  • Frequented by bumblebees and a few other bee species capable of “buzz pollinating”
  • Native people ate the fruit (preparation is undocumented)
  • CAUTION – The glycoalkaloid solanine, which is toxic to people and some animals, is in all plant parts, including leaves, fruit, and tubers, of many Solanum species

Name Derivation

  • Solanum (so- LAY-num) – from the Latin solari, “to soothe” or “to quiet,” referring to the narcotic properties of some species (e.g. Datura species)
  • umbelliferum (um-bel-IF-er-um) – from the Latin for “bearing an umbel” (a spoke-like flower cluster with stalks radiating from a single point), referring to the flower arrangement
  • Blue witch – “witches’ weeds” is a name used for some Nightshade species, as their poisonous properties made them common ingredients of potions and imagined witches’ brews
Flower (L), Developing Fruit (R)
© DSchiel


  • Nightshades (Solanum species), California poppies (Eschscholzia species), and wild roses (Rosa species) are examples of plants with nectarless flowers that offer only pollen
    • Pollen provides no immediate energy, so bees foraging on these flowers must intermittently visit nectar-bearing plants to keep their sugar buzz! (Thorp 2002)
  • Pollinated most effectively by sonication or “buzz pollination”; see Nightshade family for details
  • Flowers close at night to protect pollen
  • Drought-deciduous as well as winter-deciduous
    • Sheds leaves during the summer to conserve water
    • Stems are green, so plant can continue photosynthesis when leafless

At Edgewood

  • Found in chaparral and woodlands
  • Flowers January – September

See General References

Specific References 

Breckling, B. 2008. Spring Wildflowers of Henry W. Coe State
Park and the Inland San Francisco Bay Area
. Pine Ridge Association.

Solanaceae Source. Morphology.

Thorp. R., Schroeder, P., and Ferguson, C. 2002. Bumble Bees: Boisterous Pollinators of Native California Flowers. Fremontia 30: 3-4.