Overview
Alcea rosea 'Nigra' is a columnar upright annual biennial in the genus Alcea, part of the Malvaceae family, with deciduous foliage. It typically grows around 1.5-2.5 metres tall and 0.5-1 metres wide, reaching full size in around 1-2 years. Alcea rosea 'Nigra' grows best in full sun, and tolerates most soils and any pH. Its UK hardiness is rated H5. Suggested uses include cottage and informal garden, flower borders and beds and wall side borders. It is native to Eurasia.
About
Alcea rosea 'Nigra' (hollyhock 'Nigra') is a cultivar of the Alcea genus, known for its columnar upright habit. This herbaceous perennial or biennial typically grows to a height of 1.5 to 2.5 metres with a spread of 0.5 to 1 metre, reaching full height within one to two years. It has deciduous foliage and thrives in full sun, preferring west- or south-facing aspects. Suitable for both exposed and sheltered locations, it grows well in well-drained soils including chalk, loam, and sand, across a range of pH levels from acid to alkaline. It is of interest during spring and summer seasons.
About the genus
Alcea is a genus of over 80 species of flowering plants in the mallow family Malvaceae, commonly known as the hollyhocks. They are native to Asia and Europe. The single species of hollyhock from the Americas, the streambank wild hollyhock, belongs to a different genus.
Wikipedia contributors, "Alcea", CC BY-SA 4.0 — Alcea
Growing conditions
Best soil and position for Alcea
- Sunlight
- Full sun
- Soil type
- Chalk, Loam, Sand
- Soil pH
- Acid, Alkaline, Neutral
- Soil moisture
- Well-drained
- Aspect
- West-facing, South-facing
- Exposure
- Exposed, Sheltered
- UK hardiness
- H5
Plant details
Alcea rosea 'Nigra' size, habit and characteristics
- Plant type
- Annual Biennial, Herbaceous Perennial
- Habit
- Columnar upright
- Foliage
- Deciduous
- Height
- 1.5-2.5 metres
- Spread
- 0.5-1 metres
- Time to full height
- 1-2 years
- Suggested uses
- Cottage and informal garden, Flower borders and beds, Wall side borders
- Native to
- Eurasia
Care notes
Pruning and caring for Alcea rosea 'Nigra'
- Cultivation
- Sow seeds in spring or autumn; thin seedlings to 30 cm apart; prefers fertile, well-drained soil; mulch to retain moisture; supports may be needed for tall stems.
- Pruning
- Deadhead spent flowers to encourage further blooming; cut back to ground level after flowering to promote healthy growth next season.
- Propagation
- Seed
- Pest resistance
- Cutworms, Slugs, Capsid bugs, Aphids, Mallow flea beetles
- Disease resistance
- Hollyhock rust
Frequently asked questions
How do I grow Alcea rosea 'Nigra'?
Sow seeds in spring or autumn; thin seedlings to 30 cm apart; prefers fertile, well-drained soil; mulch to retain moisture; supports may be needed for tall stems.
Where is the best place to plant Alcea rosea 'Nigra'?
Alcea rosea 'Nigra' prefers full sun. It suits exposed and sheltered positions.
What soil does Alcea rosea 'Nigra' need?
Alcea rosea 'Nigra' is adaptable and grows happily in most soil types, including chalk, loam and sand. It is happy in soil of any pH. Aim for soil that stays well-drained.
How do I prune Alcea rosea 'Nigra'?
Deadhead spent flowers to encourage further blooming; cut back to ground level after flowering to promote healthy growth next season.
How big does Alcea rosea 'Nigra' grow?
Alcea rosea 'Nigra' reaches a height of 1.5-2.5 metres and a spread of 0.5-1 metres. It takes around 1-2 years to reach full size.
Is Alcea rosea 'Nigra' hardy in the UK?
Alcea rosea 'Nigra' has an RHS hardiness rating of H5, meaning it is hardy in most of the UK, tolerating -15 to -10°C.
How do I propagate Alcea rosea 'Nigra'?
Seed.