Overview
Trollius x cultorum 'Byrne's Giant' is a clump forming herbaceous perennial in the genus Trollius, part of the Ranunculaceae family, with deciduous foliage. Trollius x cultorum 'Byrne's Giant' grows best in full sun and partial shade, and tolerates clay and loam soils and any pH. Its UK hardiness is rated H7. Suggested uses include cottage and informal garden, wildflower meadow and flower borders and beds.
About
Trollius x cultorum 'Byrne's Giant' is a clump-forming herbaceous perennial belonging to the genus Trollius, known for their palmately lobed foliage and upright stems bearing rounded or bowl-shaped yellow flowers. This cultivar thrives in moist but well-drained, fertile soils including clay and loam, and is adaptable to a range of soil pH levels from acid to alkaline. It is hardy to UK zone H7 and flowers in spring and summer. Suitable for full sun to partial shade and various garden aspects, it is ideal for cottage gardens, wildflower meadows, and flower borders.
Growing conditions
Best soil and position for Trollius
- Sunlight
- Full sun, Partial shade
- Soil type
- Clay, Loam
- Soil pH
- Acid, Alkaline, Neutral
- Soil moisture
- Moist but well-drained, Poorly-drained
- Aspect
- South-facing, West-facing, East-facing
- Exposure
- Exposed, Sheltered
- UK hardiness
- H7
Plant details
Trollius x cultorum 'Byrne's Giant' size, habit and characteristics
- Plant type
- Herbaceous Perennial, Bogs
- Habit
- Clump forming
- Foliage
- Deciduous
- Suggested uses
- Cottage and informal garden, Wildflower meadow, Flower borders and beds
Care notes
Pruning and caring for Trollius x cultorum 'Byrne's Giant'
- Propagation
- Division in spring
- Pest resistance
- Generally pest-free
- Disease resistance
- May be susceptible to powdery mildews
Frequently asked questions
Where is the best place to plant Trollius x cultorum 'Byrne's Giant'?
Trollius x cultorum 'Byrne's Giant' prefers full sun and partial shade. It suits exposed and sheltered positions.
What soil does Trollius x cultorum 'Byrne's Giant' need?
Trollius x cultorum 'Byrne's Giant' grows best in clay and loam soil. It is happy in soil of any pH. Aim for soil that stays moist but well-drained to poorly-drained.
Is Trollius x cultorum 'Byrne's Giant' hardy in the UK?
Trollius x cultorum 'Byrne's Giant' has an RHS hardiness rating of H7, meaning it is fully hardy throughout the UK, tolerating temperatures below -20°C.
How do I propagate Trollius x cultorum 'Byrne's Giant'?
Division in spring.
More in the Trollius genus
- Trollius riederianus
- Trollius x cultorum 'Earliest of All'
- Trollius x cultorum 'Helios'
- Trollius x cultorum 'Orange Globe'
- Trollius x cultorum 'Prichard's Giant'
- Trollius 'Orange Triumph'
- Trollius 'Super Bowl'
- Trollius sinensisChinese globeflower