Hardy Geranium
Geranium spp. (e.g. 'Rozanne', G. macrorrhizum)
Hardy geraniums, or cranesbills, are tough, long-flowering perennials with lobed leaves and saucer-shaped blue, pink, purple or white flowers. They are not the same as tender pelargoniums sold as bedding "geraniums".
Photo: Alvesgaspar · CC BY-SA 3.0, via Wikimedia Commons
Essential Care Requirements
Light
Full sun, Partial sun
Watering
Moderate
Water in dry spells; many tolerate dry shade once established.
Soil
Most well-drained soils; pH 5.5–7.5.
Temperature and humidity
-35–32 °C · Moderate humidity
Feeding
Little feeding needed.
Pruning and propagation
Propagate by division
Shear back after the first flush for fresh leaves and more flowers.
Hardy geraniums are not considered toxic.
Top Cultivation Tips
'Rozanne' flowers non-stop for months.
G. macrorrhizum is great groundcover in dry shade.
Divide in spring or fall.
Hardy in USDA zones 4–8.
Common problems
Powdery mildew
A fungal disease that coats leaves, buds and young shoots with a white, flour-like dust, weakening the plant and spoiling flowers and fruit.
How to treat it →DiseaseRust
A fungal disease that forms orange, brown or yellow powdery pustules, mainly on leaf undersides.
How to treat it →PestSnails and slugs
Night-feeding molluscs that chew ragged holes in leaves, seedlings and soft stems, especially in wet weather.
How to treat it →
