Delphinium Galahad

• Variety: Galahad
• Latin name: Delphinium elatum 'Galahad' (Pacific Giant Series)
• Type: Herbaceous perennial
• Flower: Pure white with white eye
• Height: 150cm (5ft)
• Spread: 60cm (2ft)
• Flowering: June–July
• Hardiness: Fully Hardy (H7)
• Pruning: Cut back after flowering; cut to ground in autumn
• RHS AGM: No
• Sold as: Pot-grown plants
• Plant outdoors: Spring, in rich moist soil with a sheltered position
• Delivered: Spring and summer. Collection from Castle Cary also available.

Delphinium 'Galahad' is a Pacific Giant hybrid with pure white flowers and white eye, reaching 150cm in June and July. The cleanest white available in a border delphinium — luminous in evening light and one of the most effective white perennials for the back of a traditional English border.

Galahad – White, and Nothing But

Galahad is named for the purest knight in Arthurian legend — Lancelot's son, the only one capable of achieving the Holy Grail because he alone had no worldly sin — and the name suits the flower. Pure white, entirely without the blue or pink overtones that complicate the flowers of 'Astolat' or 'Black Knight', with a white eye that maintains the purity to the centre. At 150cm, a Galahad in full flower in late June catches the evening light in a way that nothing else in the border does — white flowers at height, slightly luminous as the sun drops, carrying the border's interest into dusk long after the blue and purple delphiniums have merged into the darkening garden.

White delphiniums are rare among border plants of this scale, and this is one reason Galahad earns its place even in gardens that are not particularly committed to delphiniums. As a pure vertical white element at the back, it provides what few other perennials can at this height in June — a genuine contribution to the architecture of the border, not just its colour. The same cultural requirements as all Pacific Giants apply: stake early, protect from slugs in spring, plant in rich moist soil in full sun. Generous feeding from March onwards produces the best spires.

Companions for Galahad

White delphiniums are the most versatile of the three, working with any colour scheme. Delphinium Black Knight alongside in deep violet gives the classic light-and-dark contrast. Delphinium Astolat in pink-lilac introduces warmth. For a pure white border in June — more interesting than it sounds when you consider form and texture — Campanula latifolia Alba at 120cm and Anemone Snow Angel in August provide white at different heights across the season. In front of Galahad, Lupin Gallery White provides white in May before the delphiniums emerge.

Why Ashridge?

We use peat-free compost and biological pest controls. Galahad is the white delphinium we recommend without hesitation — it performs consistently at full height and provides a genuinely distinctive contribution to the June border. Every plant is guaranteed. See the full perennial collection.

Frequently Asked Questions

Is there a white delphinium that holds the RHS AGM?

Yes — several named British cultivars hold the AGM, including 'Emily Hawkins' (pale lavender, but close to white in some lights) and the pure white 'Sandpiper'. These are vegetatively propagated named varieties at a higher price point. Galahad is seed-raised, without the AGM, but gives you reliable white at a sensible price for establishing new plantings.

Does Delphinium Galahad flower pure white or does it have a tinge?

Pure white with a white eye — there is no blue or pink tinge in the way that some "white" delphiniums have. In some years and conditions the flowers age very slightly to cream at the edges as they mature, but the overall impression at any distance is clear, unqualified white.

Will white delphiniums brighten a shaded border?

Delphiniums need full sun and are not a shade plant. In a border that receives morning sun and afternoon shade — a common situation — they can struggle to reach full height and may produce narrower spires. Save Galahad for the sunniest position available; it will repay you.

How many delphiniums do I need for an impact?

Three is a workable minimum. Five makes a proper statement. Planted in a loose group rather than a rigid line, three Galahad plants in full flower give you a column of white roughly 60–90cm wide at the back of the border — enough to anchor a mid-sized planting scheme. For very large borders, groups of five or seven in alternating varieties create the classic mixed-delphinium effect.

Should I deadhead delphiniums?

Yes — remove the main spike once it fades rather than leaving it to set seed. Then cut back to the first strong side shoots and feed with a liquid fertiliser. Side shoots can extend to give a secondary flush in August, though it is less reliable than the main June flowering. Leaving spent spires on the plant wastes energy and looks untidy.