Perennial

Agapanthus Big Blue

Agapanthus 'Big Blue'

£3.20approx. 50 seeds

Large spherical heads of deep violet-blue trumpet flowers on strong stems — the architectural African Lily that turns any sunny patio container into a piece of coastal Cornwall.

Sowing months
JanFebMarAprMayJunJulAugSepOctNovDec
Height
1–1.5m
Spread
50-100cm
Spacing
60cm
Position
Full sun — minimum 6–8 hours daily; sheltered position preferred
Soil
Fertile, moist but well-drained; does not tolerate waterlogging
Grow guide
How to grow Agapanthus Big Blue
Read the full guide →
About this variety

Agapanthus 'Big Blue' African Lily 'Big Blue'

Large, perfectly spherical flower heads of deep violet-blue trumpet flowers held high on strong, sturdy stems above clumps of elegant, strap-like evergreen foliage — 'Big Blue' is the architectural drama your sunny border or patio container has been waiting for.

If you've ever stood in a Cornish coastal garden in August and felt a pang at the sight of those fireworks-of-blue agapanthus heads, this is the variety to bring that feeling home. 'Big Blue' is an evergreen perennial, holding its broad mid-green foliage through the UK winter, and rising to 1–1.5m in summer with flower stems that need no staking even in coastal winds. Each globe-shaped umbel is composed of dozens of individual trumpet florets, each petal marked with a deeper sapphire mid-rib for a multi-tonal jewel-like effect. Famously drought-tolerant once established, virtually pest- and disease-free, and — unusually for a flowering perennial — actually flowers better when its roots are slightly congested in a pot.

A note on growing

Agapanthus from seed requires patience but is genuinely rewarding. Sow indoors in spring at 18–20°C. The seeds are larger than most flower seeds and benefit from light covering with vermiculite or fine compost. Germination is staggered — expect the first seedlings within two to three weeks but allow up to six weeks for the full batch. Pot on as the seedlings develop and grow on for at least one full season before planting out. First flowers typically appear in year three from seed; this is a long-term investment that rewards patience.

Where it shines

In sunny patio containers, where its love of slightly restricted roots makes it a natural fit, and in well-drained sunny borders where its architectural form anchors the planting. The strong stems and large heads make it exceptional as a cut flower for tall arrangements, and the dried seed heads have a sculptural quality that reads beautifully in autumn vases. Choose a sheltered, sunny spot and protect with a mulch in cold inland gardens — coastal Norfolk gardens like ours rarely need winter protection.

Plant alongside

In a coastal-style scheme, pair with silver-leaved Stachys byzantina, Lavandula, and the warm pinks of Echinacea purpurea. For a more dramatic combination, contrast the blue with the gold of Achillea 'Cloth of Gold' and the burnt orange of Crocosmia 'Lucifer'.

Plant alongside

Agapanthus Big Blue pairs beautifully with these cottage garden classics