Introducing...
Annual and biennial campanulas
Annual and biennial campanulas are ideal for giving height and soft colour to borders and containers. They will also attract beneficial insects into the garden, especially bees.
Looks
Rising from clumps of hairy leaves, upright, bristly stems are loosely arranged with bonnet-like flowers in shades of pale blue or lilac, pink, pale lemon and mauve in spring and summer. Flowers of some campanula such as Campanula medium have a saucer-like base, leading to their common name of Canterbury bells.
Likes
Grow these campanulas in any well-drained soil in sun or partial shade. They often do well in stony soil.
Dislikes
Extreme conditions are unsuitable – very wet or acidic soils, deep shade, or very dry soil in strong sunlight, which can bleach out delicate flower colours.
Did you know?
Though it’s usual to sow biennials in summer to produce plants for flowering next year, they can also be sown under cover in late winter to flower the same year.
Growing guide
How to grow annual and biennial campanulas
All the information you'll need to grow and care for annual and biennial campanulas can be found in the RHS Guide to growing annuals and biennials.
Annual campanulas we recommend
Campanula formanekiana
Macedonian harebell
- 0.1–0.5 metres
- 0.1–0.5 metres
Campanula formanekiana
Macedonian harebell
- 0.1–0.5 metres
- 0.1–0.5 metres
Useful advice
Deadheading plants
Propagation techniques
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