Crocosmia × crocosmiiflora 'Carmin Brilliant' (Montbretia) — Clump-forming, upright with arching flower sprays

Overview

Crocosmia × crocosmiiflora 'Carmin Brilliant' is a clump-forming, upright with arching flower sprays perennial in the genus Crocosmia, part of the Iridaceae family, with deciduous; stiff, pleated, sword-shaped, mid to bright green foliage. Crocosmia × crocosmiiflora 'Carmin Brilliant' grows best in full sun to partial shade, and tolerates fertile and moisture-retentive loam improved with organic matter soils and acid and neutral or alkaline pH. Its UK hardiness is rated H4-H6. Suggested uses include borders, cut flowers, cottage gardens and naturalizing in moisture-retentive soil..

About

Crocosmia × crocosmiiflora 'Carmin Brilliant' is a clump-forming perennial producing upright stems with arching sprays of flowers. The foliage is deciduous, with stiff, pleated, sword-shaped leaves in mid to bright green. It thrives in south-, west- or east-facing sites in fertile, moisture-retentive loam and is suited to sheltered positions. Flowering occurs from July to September, supplying stems for cutting or summer borders.

About the genus

Crocosmia, also known as montbretia, is a small genus of flowering plants in the iris family, Iridaceae. It is native to the grasslands of southern and eastern Africa, ranging from South Africa to Sudan. One species is endemic to Madagascar.

Wikipedia contributors, "Crocosmia", CC BY-SA 4.0 — Crocosmia

In the garden

Crocosmia × crocosmiiflora 'Carmin Brilliant' sits in the iris family (Iridaceae) and grows as a clump-forming perennial with upright growth and arching flower sprays. The leaves are stiff, pleated and sword-shaped and drop back in winter; flowering is timed from July to September, providing a concentrated late-summer display and material for the vase. Plant this montbretia in full sun to partial shade on fertile, moisture-retentive loam improved with organic matter. It accepts acid, neutral or alkaline soils so long as they remain moist but well drained; avoid waterlogged siting. A south, west or east aspect in a sheltered position will encourage the best flowering. Its UK hardiness of H4–H6 means it will persist across most UK gardens (average to very hardy), though sites that are exposed or very cold may be less reliable. Use Crocosmia × crocosmiiflora 'Carmin Brilliant' in mixed borders where tall, arching flower sprays can be displayed behind lower plants, in cottage-style beds and for cutting. It also naturalises well where soil holds moisture. Flowering stems between July and September make it a practical summer-to-early-autumn source of cut flowers.

Growing conditions

Best soil and position for Crocosmia

Sunlight: Full sun to partial shade
Soil type: Fertile, moisture-retentive loam improved with organic matter
Soil pH: Acid, neutral or alkaline
Soil moisture: Moist but well drained
Aspect: South, west or east facing
Exposure: Sheltered
UK hardiness: H4-H6

Plant details

Crocosmia × crocosmiiflora 'Carmin Brilliant' size, habit and characteristics

Plant type: Perennial
Habit: Clump-forming, upright with arching flower sprays
Foliage: Deciduous; stiff, pleated, sword-shaped, mid to bright green
Suggested uses: Borders, cut flowers, cottage gardens, naturalizing in moisture-retentive soil.

Care notes

Pruning and caring for Crocosmia × crocosmiiflora 'Carmin Brilliant'

Cultivation: Plant corms in spring rather than autumn, setting them around 10cm deep in ground that holds summer moisture, since drought during bud formation is what produces a poor showing. Clumps become congested within a few years and flowering falls away, so lift and divide regularly. The most vigorous kinds spread strongly and are best kept away from delicate neighbours; in colder gardens a dry winter mulch protects the corms.
Pruning: Remove faded flower stems, or leave the seed capsules for autumn interest. Cut the foliage down once it has yellowed in late autumn, or leave it as crown protection and clear in early spring.
Propagation: Divide congested clumps in spring, separating the chains of corms and replanting the plump upper ones. Species can be raised from seed.
Pest resistance: Little troubled outdoors; red spider mite occurs on plants under glass, and slugs graze new shoots.
Disease resistance: Robust in suitable conditions. Gladiolus rust and corm rot occur occasionally, the latter where drainage is poor.

Frequently asked questions

How do I grow Crocosmia × crocosmiiflora 'Carmin Brilliant'?

Plant corms in spring rather than autumn, setting them around 10cm deep in ground that holds summer moisture, since drought during bud formation is what produces a poor showing. Clumps become congested within a few years and flowering falls away, so lift and divide regularly. The most vigorous kinds spread strongly and are best kept away from delicate neighbours; in colder gardens a dry winter mulch protects the corms.

Where is the best place to plant Crocosmia × crocosmiiflora 'Carmin Brilliant'?

Crocosmia × crocosmiiflora 'Carmin Brilliant' prefers full sun to partial shade. It suits sheltered positions.

What soil does Crocosmia × crocosmiiflora 'Carmin Brilliant' need?

Crocosmia × crocosmiiflora 'Carmin Brilliant' grows best in fertile and moisture-retentive loam improved with organic matter soil. It prefers acid and neutral or alkaline soil. Aim for soil that stays moist but well drained.

How do I prune Crocosmia × crocosmiiflora 'Carmin Brilliant'?

Remove faded flower stems, or leave the seed capsules for autumn interest. Cut the foliage down once it has yellowed in late autumn, or leave it as crown protection and clear in early spring.

Is Crocosmia × crocosmiiflora 'Carmin Brilliant' hardy in the UK?

Crocosmia × crocosmiiflora 'Carmin Brilliant' has an RHS hardiness rating of H4, meaning it is hardy through an average UK winter, tolerating -10 to -5°C.

How do I propagate Crocosmia × crocosmiiflora 'Carmin Brilliant'?

Divide congested clumps in spring, separating the chains of corms and replanting the plump upper ones. Species can be raised from seed.

More in the Crocosmia genus

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