When to plant Canterbury Bells in Cool Australia

Cool zone — applies to Hobart, Canberra, Ballarat, Orange, Armidale and similar areas. Growing elsewhere? Temperate · Subtropical · Tropical · Arid.

Raise Canterbury bells from seed sown in February, March or April, pressing the fine seed only 3 mm into trays and leaving it uncovered, as light aids germination. Sprouting is slow and erratic at 7–28 days, so be patient. This biennial takes a long 140–160 days to reach its tall spires of bell-shaped flowers, forming a leafy rosette in the first season and flowering the next. Transplant seedlings 30 cm apart in each direction into a sunny or lightly shaded, well-drained bed. Autumn sowing lets the young plants establish and vernalise over winter, ready to bloom the following spring and summer.

Sowing calendar — cool zone

Green months are your sowing window: February to April.

Growing notes

Canterbury bells is a classic cottage biennial that suits the cool gardens of Hobart, Orange and Armidale, where reliable winter cold triggers the flowering it depends on. Because it is a biennial, patience is the price of admission: sown in autumn, it makes only a low rosette of leaves in the first year, needs a cold winter to vernalise, and rewards you with flower spikes the following spring and summer. The most common disappointment is expecting blooms in the first season, which will not happen.

Beyond patience, the main failure mode is crown rot from wet winter soil. The rosettes sitting through a cold, damp winter will rot if drainage is poor, so plant into free-draining ground, or raise the bed, and avoid mulching right up against the crowns.

Stake the tall flower stems as they rise, since they catch the wind and can snap or flop after rain. Keep the plants evenly watered through their flowering flush and deadhead spent spikes to prolong the display. Once flowering finishes, the plant sets seed and dies, so let a few heads ripen if you want a self-sown succession. Slugs and snails favour the soft rosettes, so protect young plants over their first winter.

Canterbury Bells at a glance

Common questions

how long do Canterbury bells take to flower

Canterbury bells is a biennial and takes roughly 140–160 days across two seasons. Sown in autumn, it makes a leafy rosette in the first year and flowers the following spring and summer after a cold winter. Do not expect blooms in the first season.

when to sow Canterbury bells seeds

Sow in autumn, from February to April, so the young plants establish and vernalise over winter for flowering the next year. Press the fine seed only 3 mm in and leave it uncovered, as light helps germination. Cool-climate winters provide the cold the plant needs to set flower.

why did my Canterbury bells rot over winter

Crown rot in the overwintering rosettes is caused by wet, poorly drained soil. Plant into free-draining ground or raise the bed, and keep mulch away from the crowns so they don't sit damp. Good drainage through a cold, wet winter is the key to getting them through to flower.

do Canterbury bells come back every year

As a true biennial, each plant flowers once in its second year and then dies after setting seed. To keep a display going, sow every year, or let a few flower heads ripen and drop seed so new rosettes replace the old plants. This gives you a self-sustaining succession over time.

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