Allium cristophii

A truly spectacular ornamental allium, Allium cristophii, also known as the Star of Persia, is prized for its enormous open flower heads made up of shimmering metallic lilac-purple star-shaped florets.

Unlike the dense globes of many alliums, this variety forms large airy umbels that can reach up to 20 cm across, creating a dramatic architectural effect in the garden. Each individual flower catches the light beautifully, giving the blooms a sparkling almost iridescent appearance.

Native to the dry mountainous regions of Turkey and Iran, Allium cristophii has been grown in ornamental gardens since the late 19th century and remains one of the most admired alliums for its unique form and striking texture.

Flowering in late spring and early summer, it works beautifully in sunny borders, gravel gardens and prairie-style planting schemes, where the huge starry flower heads appear to float above surrounding plants. The blooms are highly attractive to bees and pollinators, while the dried seed heads remain decorative long after flowering has finished.

Perfect for adding bold structure and natural elegance, this easy-to-grow allium is a true statement plant for the summer garden.

RHS Award of Garden Merit.

Allium cristophii has been awarded the RHS Award of Garden Merit because it has proved to be reliable in appropriate conditions and a good performing plant. 

Planting Instructions

When to Plant:

Plant Allium bulbs in autumn (September–November) before the ground freezes. This allows roots to establish for strong flowering the following season.

Where to Plant:
Choose a sunny position with well-drained soil. Alliums are ideal for borders, gravel gardens and naturalistic planting schemes. Avoid areas where soil remains wet over winter.

How to Plant:

• Depth: Plant bulbs about 10–15 cm (4–6 inches) deep.
• Spacing: Space bulbs about 15–20 cm (6–8 inches) apart.
• Soil Prep: Improve soil with compost. In heavier soils, add grit or sharp sand to improve drainage.

Watering:
Water after planting. Once established, Alliums require very little additional watering unless conditions are particularly dry.

Aftercare Tips:

• Allow foliage to die back naturally after flowering to feed the bulb.
• Leave seed heads standing for long-lasting ornamental interest.
• Avoid excessive moisture in winter to prevent bulb rot.

Top Tip:
Plant in groups amongst ornamental grasses or low perennials to fully appreciate the huge starburst flower heads and their beautiful dried seed structures.

Plant Details

Flowering Period:
June - July (depending on season and conditions)

Height:
10–24" (25–60cm) (approx.)

Position:
Full sun

Hardy Perennial