Delphinium Benary’s Pacific King Arthur | Delphinium hybrida

Delphinium hybrida ‘Benary’s Pacific King Arthur’ is a magnificent tall perennial Delphinium prized for its deep violet-blue flowers with contrasting white centres and impressive, upright flower spikes.

Part of the renowned Benary’s Pacific series, King Arthur combines the dramatic appearance of traditional tall Delphiniums with excellent qualities for cut flower production. The series has been rigorously tested for flower and stem quality and produces long, impressive stems with excellent vase life.

An important advantage is its FastraX perennial characteristic: plants can flower in the first year from seed without vernalization, making King Arthur particularly interesting for both professional cut flower growers and home gardeners.

Plant Information

• Botanical name: Delphinium hybrida
• Series: Benary’s Pacific
• Variety: King Arthur
• Plant type: Perennial
• Height: Approx. 160 cm
• Flower colour: Deep violet-blue with white centre
• Flowering: Summer
• First-year flowering: Yes
• Vernalization required: No
• Position: Full sun to partial shade
• Seed form: Raw seed
• Uses: Cut flower, cutting garden, perennial borders and landscape planting
• Vase life: Long

Dramatic Violet-Blue Flowers

King Arthur produces spectacular, tall flower spikes covered with rich violet-blue flowers highlighted by contrasting white centres.

The combination of intense colour and a pale centre gives individual flowers extra depth, while the long vertical spikes create a dramatic architectural effect.

In the garden, King Arthur provides height and structure at the back of perennial borders. For floristry, its long stems are especially valuable for large bouquets, garden-style arrangements and statement floral designs.

How Long from Seed to Flower?

Under suitable spring growing conditions:

18–22 weeks = approximately 126–154 days from sowing to flowering.

Benary’s Pacific King Arthur belongs to the FastraX perennial programme, meaning plants are capable of flowering in their first year from seed without requiring a cold period beforehand.

Actual crop time can vary depending on sowing date, temperature, light intensity and day length.

First-Year Flowering Without Vernalization

Traditional perennial Delphiniums are often associated with waiting until the following season for their best flowering.

King Arthur offers an important advantage:

Vernalization is not required for first-year flowering.

When seeds are started sufficiently early and plants receive suitable growing conditions, they can produce their impressive flower spikes during the first growing season.

This makes the variety particularly useful for growers who want to produce perennial Delphiniums from seed within one season.

Sowing & Germination

Sow 2–3 seeds per plug in a fine, well-drained seed-starting substrate.

Cover the seeds lightly with vermiculite or a thin layer of substrate.

Keep the substrate consistently moist during the initial germination period, but avoid waterlogging.

For reliable production, young plants benefit from moderate temperatures, good air circulation and plenty of light once seedlings have emerged.

Growing the Young Plants

Once established, provide the seedlings with bright light and good ventilation.

Water carefully, allowing the growing medium to dry slightly between waterings rather than keeping it continuously saturated.

Delphiniums develop best when young plants are grown steadily rather than being subjected to excessive heat or overfeeding.

Before planting outdoors, gradually harden the plants to outside conditions.

Position & Soil

Plant King Arthur in full sun to partial shade.

Choose a fertile, humus-rich and well-drained soil that retains moisture without becoming waterlogged.

Incorporating mature compost before planting can improve both soil structure and nutrient availability.

Because King Arthur develops very tall flower stems, a position protected from strong winds is beneficial.

Tall Plants Need Support

With flower stems reaching approximately 160 cm, King Arthur is a genuinely tall Delphinium.

Providing stakes, support netting or another plant support system is recommended, especially in exposed gardens and professional cut flower fields.

Early support allows the stems to grow straight and helps prevent damage from strong wind or heavy rain.

Watering & Feeding

Maintain relatively consistent soil moisture during active growth and particularly while the long flower spikes are developing.

During dry periods, water deeply rather than frequently applying only small amounts of water.

Delphiniums appreciate fertile soil and balanced nutrition. Avoid excessive feeding, particularly excessive nitrogen, which can encourage overly soft growth.

Exceptional Cut Flower

Benary’s Pacific has been rigorously tested for excellent flower and stem quality.

For cut flower growers, King Arthur offers:

Long, impressive stems • Strong vertical flower spikes • Excellent flower quality • Rich violet-blue colour • Long vase life

The combination of height and colour makes King Arthur particularly useful when a strong vertical element is needed in floral arrangements.

It can be grown for cutting in the field, under tunnels or in a greenhouse.

When to Cut Delphinium

Harvest the stems when the lower flowers on the spike have opened while the upper section still contains unopened buds.

Place freshly harvested stems into clean water as soon as possible.

The long stems make King Arthur particularly valuable for large-scale arrangements and taller bouquets where shorter Delphinium varieties may not provide enough height.

A Delphinium for Professional Cut Flower Growing

King Arthur is particularly interesting for growers looking for a tall perennial Delphinium from seed.

At approximately 160 cm, it is considerably taller than the more compact Magic Fountains series and therefore provides a different type of cut stem.

Where Magic Fountains is useful when a more manageable plant height is desired, Benary’s Pacific King Arthur is the choice for long, dramatic flower stems.

In the Garden

King Arthur creates a striking vertical accent in perennial borders and cottage-style gardens.

Because of its height, plant it toward the middle or back of the border, where its tall violet-blue flower spikes can rise above lower-growing perennials.

It combines beautifully with roses, foxgloves, campanulas and other traditional cottage-garden plants.

Why Choose Benary’s Pacific King Arthur?

Deep violet-blue flowers • Contrasting white centres • Approx. 160 cm tall • Long and impressive flower stems • Perennial • Flowers in the first year • No vernalization required • Excellent cut flower • Long vase life

Perfect for

Cut flowers • Professional cut flower production • Cutting gardens • Perennial borders • Cottage gardens • Large floral arrangements • Landscape planting

Delphinium hybrida ‘Benary’s Pacific King Arthur’ is an excellent choice for growers looking for a tall, first-year flowering perennial Delphinium with spectacular violet-blue flowers, contrasting white centres and exceptionally long stems for cutting.