Delphinium cheilanthum (garland larkspur) — perennial

Overview

Delphinium cheilanthum is a perennial in the genus Delphinium, part of the Ranunculaceae family. Delphinium cheilanthum grows best in full sun and partial shade, and tolerates well-drained and loamy soils and neutral and slightly acidic pH. Its UK hardiness is rated H5. Suggested uses include borders, cut flowers and rock gardens. It is native to California and USA.

About

Delphinium cheilanthum is a perennial larkspur that flowers in the UK from June to August. It originates from California and suits a south-facing, sheltered planting position. Plant in moist, well-drained loamy soil with a neutral to slightly acidic pH and give full sun or partial shade. All parts of the plant are toxic, so avoid placing it where children or livestock can reach it.

About the genus

Delphinium is a genus of about 300 species of annual and perennial flowering plants in the family Ranunculaceae, native throughout the Northern Hemisphere and also on the high mountains of tropical Africa. The genus was erected by Carl Linnaeus.

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

In the garden

Delphinium cheilanthum is a perennial member of the Ranunculaceae native to California, USA, brought into cultivation for its summer display. In the UK it reliably flowers from June to August and is grown where late-spring into mid-summer colour is wanted. The species belongs to the Delphinium genus and is commonly called garland larkspur. Choose a south-facing, sheltered site to reduce wind damage to flowering stems and to maximise flowering. It prefers moist but well-drained loamy soil with a neutral to slightly acidic reaction; avoid waterlogged or very dry locations. Give plants a position in full sun or light afternoon shade. It is classed H5, meaning it is hardy for most British gardens when sited out of exposed conditions. Use garland larkspur towards the back of a mixed border, in a sheltered rock-garden niche or as a source of summer cut flowers. Because all parts are toxic, locate it away from children’s play areas and stock grazing. For cutting, take flowering stems while the lower florets are opening between June and August so you capture the display at its best.

Growing conditions

Best soil and position for Delphinium

Sunlight: full sun, partial shade
Soil type: well-drained, loamy
Soil pH: neutral, slightly acidic
Soil moisture: moist
Aspect: south-facing
Exposure: sheltered
UK hardiness: H5

Plant details

Delphinium cheilanthum size, habit and characteristics

Plant type: perennial
Suggested uses: borders, cut flowers, rock gardens
Native to: California, USA
Toxicity: toxic

Care notes

Pruning and caring for Delphinium cheilanthum

Cultivation: Prefers well-drained soil with consistent moisture; avoid waterlogging. Mulch to retain moisture and protect roots in winter.
Pruning: Deadhead spent flowers to encourage further blooming; cut back foliage after flowering to promote healthy growth.
Propagation: seed,division

Frequently asked questions

How do I grow Delphinium cheilanthum?

Prefers well-drained soil with consistent moisture; avoid waterlogging. Mulch to retain moisture and protect roots in winter.

Where is the best place to plant Delphinium cheilanthum?

Delphinium cheilanthum prefers full sun and partial shade. It suits sheltered positions.

What soil does Delphinium cheilanthum need?

Delphinium cheilanthum grows best in well-drained and loamy soil. It prefers neutral and slightly acidic soil. Aim for soil that stays moist.

How do I prune Delphinium cheilanthum?

Deadhead spent flowers to encourage further blooming; cut back foliage after flowering to promote healthy growth.

Is Delphinium cheilanthum hardy in the UK?

Delphinium cheilanthum 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 Delphinium cheilanthum?

Seed,division.

Is Delphinium cheilanthum toxic?

Toxic.

More in the Delphinium genus

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