Perennials
Aconitum cammarum 'Bicolor'
Bicolor Hybrid Monkshood
Ranunculaceae
Europe (hybrid origin; parent species from central and western Europe)
At a Glance
TypePerennial
HabitUpright
FoliageDeciduous
Height3–5 feet (90–150 cm)
Width18–24 inches (45–60 cm)
Maturity2 years
Growing Zones
USDA Hardiness Zones
3 - 7Zone 3
Zone 4
Zone 5
Zone 6
Zone 7
These zones indicate the coldest temperatures this plant can typically survive.
Frost Tolerancehardy
Key Features
Attracts Pollinators
Deer Resistant
Maintenancemoderate
Overview
Aconitum cammarum 'Bicolor' is an upright herbaceous perennial reaching 3–5 feet (90–150 cm) tall with a spread of 18–24 inches (45–60 cm), forming an erect clump of deeply divided foliage topped by racemes of hooded bicolor flowers. Aconitum cammarum is the accepted name for the hybrid complex between A. napellus and A. variegatum; 'Bicolor' is the cultivar name applied to white-and-blue-violet selections within this complex and is taxonomically equivalent to plants sometimes listed as Aconitum bicolor. Leaves are palmately divided, 3–6 inches (7.5–13 cm) wide, with five to seven deeply lobed and sharply serrated segments, dark glossy green. Flowers are white with blue-violet to purple margins and hood, arranged in elongated racemes 12–18 inches (30–45 cm) long from July through August. Stems are erect and may require staking at the taller end of the height range. All parts contain aconitine alkaloids and are highly toxic to humans, pets, and livestock.
Native Range
Aconitum cammarum is a hybrid complex involving A. napellus and A. variegatum, both native to mountain meadows, stream margins, and open woodland edges in central and western Europe at elevations of 2,500–8,000 feet (750–2,400 m). The 'Bicolor' cultivar is of garden selection and does not occur in wild populations.Suggested Uses
Planted in partially shaded borders, woodland garden edges, and stream-side plantings at 18–24 inch (45–60 cm) spacing. The bicolor white-and-blue-violet flowers extend the shade border season into late summer. Suited to zones 3–7 in consistently moist, cool sites. Not suited to dry soils, hot-summer climates without afternoon shade, or gardens accessible to unsupervised children or grazing animals.How to Identify
Appearance
Size & Dimensions
Height3' - 5'
Width/Spread1'6" - 2'
Reaches mature size in approximately 2 years
Colors
Flower Colors
white
blue
purple
Foliage Colors
dark green
Fall Foliage Colors
no change
Bloom Information
Bloom Period
~7 weeksJ
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Summer
Detailed Descriptions
Flower Description
white with blue-violet to purple hood and marginsFoliage Description
dark glossy greenGrowing Conditions
Sun Requirements
Partial Shade
Full Shade
Requires 2-6 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 - 7.0(Neutral)
357912
Soil Types
loamclay
Drainage
moist
Water & Climate
Water Needs
High
Frost Tolerance
hardy
Time to Maturity
2–3 years
Care & Maintenance
Care Guide
Plant in moist, well-drained, humus-rich soil with a pH of 5.5–7.0 in partial shade to full sun where summers are cool. Afternoon shade reduces heat stress where temperatures exceed 75°F (24°C). Water consistently — do not allow the soil to dry out; water weekly during dry periods. Mulch to retain soil moisture and keep the root zone cool. Performs in zones 3–7. Divide clumps every 3–4 years in early spring to maintain vigor. All parts are highly toxic — wear gloves when handling.Pruning
Cut stems to the ground in late fall after frost. Deadhead spent racemes after bloom to tidy the plant; a second flush of smaller racemes sometimes follows. Divide in early spring before significant foliage emergence. Wear gloves — all parts contain aconitine alkaloids.Pruning Schedule
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fallearly spring