Geranium phaeum 'Samobor' (Samobor Geranium)

Wouterhagens, no rights reserved (CC0) · Wikimedia Commons

1 / 5

Geranium phaeum 'Samobor'

Samobor geranium

Geraniaceae

Collected near Samobor, Croatia; C and S Europe (Pyrenees to Balkans)

Attracts Pollinators Deer Resistant Drought Tolerant Container Friendly

SunPart Shade – Full Shade

WaterMedium · drought-tolerant

HardinessZones 4–8

Overview

Geranium phaeum 'Samobor' is an upright clumping deciduous perennial reaching 18–24 inches (45–60 cm) tall with a spread of 18–24 inches (45–60 cm). The cultivar was collected from wild populations near the town of Samobor in Croatia, west of Zagreb, and is grown primarily for its foliage rather than its flowers. The broad palmately 7–9 lobed leaves, 4–6 inches (10–15 cm) across, carry a prominent dark chocolate-brown to maroon-purple zone that forms a broad ring on each leaf at the junction between the lobes and the central portion—no other phaeum spp. cultivar in commerce carries such pronounced dark leaf blotching. Flowers match the typical species form: small nodding blooms with reflexed petals, 0.75–1 inch (2–2.5 cm) across, dark maroon-purple to near-black (the mourning widow color from which the species common name derives). Bloom runs from May through July over a 6–8 week window. The combined dark-blotched foliage and near-black flowers produce a strongly dark-toned garden effect that suits shadow-garden compositions and foliage-driven shaded plantings. Shade tolerance runs deep. Hardy to zone 4.

Native Range

Geranium phaeum is native to central and southern Europe (Pyrenees, Alps, Carpathians, Balkans). 'Samobor' was collected from wild populations near the town of Samobor in Croatia, west of Zagreb in the Žumberak–Samoborsko Gorje nature park region. The cultivar was introduced to horticultural commerce through English nursery trade after its wild collection.

Suggested Uses

Planted in woodland gardens and shaded borders at 18–24 inch (45–60 cm) spacing. Grown primarily as a foliage perennial rather than a flowering one, the dark chocolate-maroon leaf markings contribute season-long foliage interest beyond the 6–8 week bloom period itself. The dark-toned foliage pairs effectively with lighter-leaved companions—ferns (Polystichum spp., Dryopteris spp.), hostas (Hosta spp. 'Halcyon'), and Brunnera macrophylla 'Jack Frost'—where the dark zoning carries contrast value against lighter green or silver-variegated foliage. Functions in deep shade positions under mature deciduous canopy. Self-seeding naturalizes the cultivar into surrounding planting areas over time. Full hot summer sun and dry exposed positions are poor fits for the cultivar.

How to Identify

Separated from 'Joan Baker' by the prominent dark chocolate-brown to maroon leaf blotches (versus plain bright green foliage) and by the dark maroon-purple-to-near-black (versus pale mauve-pink) flower color. The foliage zoning is the cultivar's primary identification feature; the broad dark ring on each leaf appears on no other widely grown G. phaeum cultivar and runs through the full growing season. A phaeum spp. with broad chocolate-maroon leaf zones and dark near-black reflexed flowers identifies this cultivar.

Appearance

Size & Dimensions

Height1'6" - 2'

Width/Spread1'6" - 2'

Reaches mature size in approximately 2 years

Colors

Flower Colors

Foliage Colors

Fall Foliage Colors

Bloom Information

Bloom Period

~7 weeks

Spring Summer

Small nodding flowers 0.75–1 inch (2–2.5 cm) across with reflexed petals, dark maroon-purple to near-black (the mourning widow color from which G. phaeum takes its common name), open on slender branching stems from May through July. Bloom duration is 6–8 weeks. The dark flowers read subtly against the dark-marked foliage and show more clearly when viewed at close range than from garden distance.

Detailed Descriptions

Flower Description

Dark maroon-purple to near-black; reflexed petals; nodding

Foliage Description

Green with prominent dark chocolate-brown to maroon-purple ring/zone; broad palmately lobed

Growing Conditions

Sun Requirements

SunPartial Shade SunFull Shade

Requires 1-5 hours of direct sunlight daily

• Full Sun: 6+ hours of direct sunlight

• Partial Shade: 3-6 hours of direct sunlight

• Full Shade: Less than 3 hours of direct sunlight

Soil Requirements

pH Range5.5 - 7.5(Neutral)

357912

Soil Types

loam clay

Drainagemoist

Water & Climate

Water Needs

Medium

Frost Tolerance

hardy

Time to Maturity

1-2 years

Drought Tolerance

Drought tolerant when established

Care & Maintenance

Care Guide

Partial shade to full shade in moist humus-rich well-drained soil matches the cultivar's needs. Hardy to zone 4 (−30°F / −34°C). Leaf-marking contrast runs strongest in bright shade positions where the foliage receives filtered light; deep shade can reduce the visual contrast between the dark zone and the green surrounding tissue. Self-seeding in favorable conditions runs vigorous, so deadheading is used where unwanted seedlings need to be controlled. Dry shade is tolerated once the root system establishes through the first 1–2 seasons of regular watering.

Pruning

Flower stems are cut back after blooming finishes (late July or August) to prevent self-seeding and to encourage fresh basal foliage that carries the strongest leaf-zone coloration through the second half of the growing season. Old foliage is cut to the ground in late fall or early spring.

Pruning Schedule

summer