Overview
Heracleum maximum is a bushy annual biennial in the genus Heracleum, part of the Apiaceae family, with semi evergreen foliage. Heracleum maximum grows best in full sun and partial shade, and tolerates loam soils and neutral pH. Its UK hardiness is rated H7. Suggested uses include wildlife gardens and wildflower meadow.
About
Heracleum maximum, commonly known as American cow parsnip or American masterwort, is a bushy, semi-evergreen herbaceous plant within the Apiaceae family. As a member of the Heracleum genus, which includes species such as giant hogweed and cow parsley, it thrives in fertile, well-drained loam soil with neutral pH and moist conditions. This hardy plant (H7) prefers full sun to partial shade and can be grown in exposed positions facing any direction. It is suitable for wildlife gardens and wildflower meadows, with interest during spring and summer. Propagation is by seed or division.
Growing conditions
Best soil and position for Heracleum
- Sunlight
- Full sun, Partial shade
- Soil type
- Loam
- Soil pH
- Neutral
- Soil moisture
- Moist but well-drained
- Aspect
- East-facing, North-facing, South-facing, West-facing
- Exposure
- Exposed
- UK hardiness
- H7
Plant details
Heracleum maximum size, habit and characteristics
- Plant type
- Annual Biennial, Herbaceous Perennial
- Habit
- Bushy
- Foliage
- Semi evergreen
- Suggested uses
- Wildlife gardens, Wildflower meadow
Care notes
Pruning and caring for Heracleum maximum
- Propagation
- Seed, Division
Frequently asked questions
Where is the best place to plant Heracleum maximum?
Heracleum maximum prefers full sun and partial shade. It suits exposed positions.
What soil does Heracleum maximum need?
Heracleum maximum grows best in loam soil. It prefers neutral soil. Aim for soil that stays moist but well-drained.
Is Heracleum maximum hardy in the UK?
Heracleum maximum has an RHS hardiness rating of H7, meaning it is fully hardy throughout the UK, tolerating temperatures below -20°C.
How do I propagate Heracleum maximum?
Seed, Division.
More in the Heracleum genus
- Heracleum lehmannianumLehmann's hogweed
- Heracleum mantegazzianumgiant hogweed
- Heracleum nepalense
- Heracleum panacesHercules' woundwort
- Heracleum sphondylium 'Pink Cloud'
- Heracleum sphondylium var. angustifolium
- Heracleum steveniiSteven's hogweed
- Heracleum villosumgiant cow parsnip
