Hardy Geranium, Cranesbill 'Nimbus'


Family: Geraniaceae (jer-ay-nee-AY-see-ee) (Info)
Genus: Geranium (jer-AY-nee-um) (Info)
Cultivar: Nimbus
Hybridized by Cambridge University Botanic Garden
Registered or introduced: 1990
» View all varieties of Hardy Geraniums


Alpines and Rock Gardens


Water Requirements:

Average Water Needs; Water regularly; do not overwater

Sun Exposure:

Full Sun

Sun to Partial Shade



Foliage Color:

Unknown - Tell us


18-24 in. (45-60 cm)


15-18 in. (38-45 cm)


USDA Zone 4a: to -34.4 C (-30 F)

USDA Zone 4b: to -31.6 C (-25 F)

USDA Zone 5a: to -28.8 C (-20 F)

USDA Zone 5b: to -26.1 C (-15 F)

USDA Zone 6a: to -23.3 C (-10 F)

USDA Zone 6b: to -20.5 C (-5 F)

USDA Zone 7a: to -17.7 C (0 F)

USDA Zone 7b: to -14.9 C (5 F)

USDA Zone 8a: to -12.2 C (10 F)

USDA Zone 8b: to -9.4 C (15 F)

USDA Zone 9a: to -6.6 C (20 F)

USDA Zone 9b: to -3.8 C (25 F)

Where to Grow:

Unknown - Tell us



Bloom Color:



Bloom Characteristics:

This plant is attractive to bees, butterflies and/or birds

Bloom Size:

Unknown - Tell us

Bloom Time:

Late Spring/Early Summer

Mid Summer

Late Summer/Early Fall

Other details:

Unknown - Tell us

Soil pH requirements:

5.6 to 6.0 (acidic)

6.1 to 6.5 (mildly acidic)

6.6 to 7.5 (neutral)

7.6 to 7.8 (mildly alkaline)

7.9 to 8.5 (alkaline)

Patent Information:


Propagation Methods:

By dividing the rootball

By dividing rhizomes, tubers, corms or bulbs (including offsets)

From herbaceous stem cuttings

From seed; direct sow outdoors in fall

From seed; winter sow in vented containers, coldframe or unheated greenhouse

From seed; stratify if sowing indoors

From seed; sow indoors before last frost

Self-sows freely; deadhead if you do not want volunteer seedlings next season

Seed Collecting:

Bag seedheads to capture ripening seed

Allow seedheads to dry on plants; remove and collect seeds


This plant has been said to grow in the following regions:

North Egremont, Massachusetts

Northfield, Vermont

Langley, Washington

Spokane, Washington

Vancouver, Washington

Muscoda, Wisconsin

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Gardeners' Notes:


On Oct 18, 2014, coriaceous from ROSLINDALE, MA wrote:

Can get over 2' tall. This is a sterile hybrid (G. collinum x G. clarkei 'Kashmir purple'). Sporadic rebloom is better in cool-summer climates.

The Royal Horticultural Society has granted this cultivar its coveted Award of Garden Merit (AGM).


On Jul 2, 2010, microcollie from North Egremont, MA wrote:

I have countless geraniums in my gardens, and this is my favorite. Its finely-cut foliage is always beautiful, and it blooms profusely. It does get big, so give it room...one of mine has a good six foot spread. Hovever, it looks great winding through its neighbors. Probably not a plant for those who like very strict order in their beds, with no plants touching, but in an informal setting, its perfect. If it gets out of control or slows down on blooming, it can be cut back sharply without damage and sets new blooms rapidly.


On Mar 21, 2007, berrygirl from Braselton, GA (Zone 8a) wrote:

GERANIUM Nimbus-Cranesbill - Medium 20" - Plant 16" apart. zone 4-8. Arguably as good, or better than G. Johnson's Blue. Very floriferous and vigorous. Lavender blue flowers with a violet center over attractive mounds of dissected leaves.

General Information:
Mounded in form. Cranesbill is a favorite for its excellent habit, and late spring to summer blooming period. Flowers remain nestled among the leaves.

Plant Care:
Can be cut back hard after the first main bloom, or at any time, and will soon leaf out and even bloom again.