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Dusky Geranium

Dusky geranium cultivar Samobor

Dusky geranium is often sold as Mourning widow geranium due to the dark purple flowers.  The popular cultivar 'Samobor' also features a ring of dark purple on its leaves.  Dusky geranium is well adapted to shady sites.

This plant has some cultivated varieties. Go to list of cultivars.


Botanical name:

Geranium phaeum

All Common Names:

Dusky geranium, mourning widow, dusky crane's-bill, black widow

Family (English):


Family (Botanic):


Tree or Plant Type:

  • Ground cover,
  • Perennial

Native Locale:

  • Non-native

Landscape Uses:

  • Container,
  • Massing,
  • Mixed border

Size Range:

  • Large plant (more than 24 inches),
  • Medium plant (12-24 inches)

Light Exposure:

  • Partial sun/shade (4-6 hrs light daily),
  • Full shade (4 hrs or less of light daily)

Hardiness Zones:

  • Zone 4,
  • Zone 5 (Chicago),
  • Zone 6,
  • Zone 7

Soil Preference:

  • Moist, well-drained soil


  • Alkaline soil,
  • Clay soil

Season of Interest:

  • Late spring,
  • Early summer

Flower Color & Fragrance:

  • Purple

Shape or Form:

  • Broad,
  • Upright

Growth Rate:

  • Fast

More Information:

Size and Method of spreading

Dusky geranium grows 1 1/2 to 2 1/2 feet tall when in flower.  Spread can be 1 to 1 1/2 feet.  This is a clump-forming ground cover.  Clump-forming ground covers are perennials that can be planted closely together to provide the visual effect of a ground cover.  This species also spreads to some degreen through short rhizomes and self seeding.

Plant Care

This ground cover does well in partial to full shade situations.  It prefers a moist, well drained soil, but wil tolerate some dryness.  Excessive heat can cause the foliage to dieback.  This geranium self seeds readily and deadheading can control unwanted seedlings.

Disease, pests, and problems

No serious disease or insect problems.

Native geographic location and habitat

Native to Europe; commonly found in wooded areas.

Leaf description

The leaves are lobed, with jaggedly toothed margins.  The general outline of the leaf is rounded.  The leaves of the species are green, but some cultivars have purple-banded leaves.

Flower description

The flowers of this species are small (about 1 inch), with 5 petals.  They are a dark maroon or purple.   The flowers are held above the foliage.  Most of the flowering occurs in early summer.

Fruit description

Fruits are beaked capsules said to resemble a cranes bill.  Not ornamentally important.


Cultivars and their differences 

Raven dusky geranium (Geranium phaeum 'Raven'):  Very dark purple flowers with a white eye.

Samobor dusky geranium (Geranium phaeum 'Samobor'):  Maroon-purple flowers; foliage with a purple band.


Location of Geranium phaeum (Dusky Geranium) at the Arboretum

We do not seem to have this in our living collection.