Granny's bonnet

Sun

Full sun to partial shade; afternoon shade is best where summers are hot.

Water

Moderate; keep the soil evenly moist while plants establish and during prolonged dry spells, without leaving it waterlogged.

Soil

Moist but well-drained soil enriched with organic matter; tolerates clay, loam and chalk if drainage is adequate.

Height

2-3 ft (0.6-0.9 m)

Spread

1-1.5 ft (0.3-0.45 m)

Flowers

Late spring to early summer; the species is usually violet-blue, with garden forms in purple, pink, red or white, sometimes bicoloured or double.

Foliage

Blue-green leaves divided into rounded, scalloped leaflets; the basal clump may become untidy or die back after flowering in hot, dry weather.

Growth

Moderate; usually flowers in its second year from seed.

Care needed

Low

• Pollinators
• Deer resistant
• Cold hardy
• Low allergen

Northern hemisphere months. In Australia, shift them by six.

Difficulty

Easy

Toughness

Fairly tough

Pick your zone, country, light and whether you have pets.

1. Planting day

   1 ft (0.3 m)

2. After 1 year

   1.5 ft (0.45 m)

3. After 2 years

   2 ft (0.6 m)

4. After 3 years

   2.5 ft (0.75 m)

   full size

About 3 years to full size.

From a typical nursery size, at an average rate for this kind of plant. A rule of thumb, not a forecast.

Cats and dogs

Safe

Native to

the UK

In the garden

Spreads vigorously: plan to contain it.

Growth rate

Moderate

• Water new plants regularly through their first growing season.
• Water established plants during extended dry spells, especially while flowering.
• Apply a thin layer of compost in spring; rich feeding is usually unnecessary.
• Mulch to conserve moisture, keeping mulch clear of the crown.
• Thin unwanted seedlings and retain a few healthy young plants to replace ageing clumps.

Pruning. Cut spent flower stems down to the basal leaves unless you want seed. After flowering, cut badly mildewed or leaf-mined foliage back to healthy growth, and remove dead foliage in late autumn or early spring.

Early spring

Remove dead foliage and apply a thin layer of compost around established plants.

Spring

Plant nursery-grown plants and move small self-sown seedlings before their roots become well established.

Late spring

Water during dry weather and check leaves for mining damage or caterpillar-like sawfly larvae.

Early summer

Deadhead fading flowers, leaving a few stems only if you want seedlings.

Summer

Collect ripe seed before the pods open, sow it fresh, and cut back badly damaged foliage.

Autumn

Thin crowded seedlings and plant out young plants while the soil is moist.

• Thread through cottage borders with hardy geraniums and foxgloves for an informal late-spring display.
• Plant along lightly shaded woodland edges with ferns and brunnera.
• Use among roses and peonies, where its slender flower stems add height without a dense mass of foliage.
• Allow a controlled scattering of seedlings through mixed borders to link separate planting groups.

Garden styles it suits: Cottage garden, English country, Romantic rose garden, Woodland, Wildlife garden and Arts and Crafts.

Plant it with: Hardy geraniums, Foxgloves, Brunnera, Lady's mantle, Peonies and Ferns.

Wildlife: The flowers provide nectar and pollen for bees, particularly long-tongued bumblebees. Single flowers are generally more accessible than heavily doubled forms.

• Leaf miners leave pale winding trails or blotches in leaves. Remove badly affected leaves; established plants usually tolerate the damage without spraying.
• Columbine sawfly larvae can strip leaves quickly. Inspect plants regularly and pick off larvae by hand.
• Powdery mildew produces a white coating on foliage. Improve airflow, water the soil rather than the leaves, and remove badly affected foliage.
• Aquilegia downy mildew causes yellow angular patches, distorted growth and sometimes downy growth beneath leaves. Remove and dispose of infected plants rather than composting them, and avoid propagating from affected stock.

Potentially harmful to people if eaten, especially the seeds and roots; do not use any part as food. It is not generally classified as toxic to cats, dogs or horses, but this does not make it suitable for feeding, and chewing plant material can cause stomach upset. Seek medical or veterinary advice after a significant ingestion or if symptoms develop.

Where it spreads. Can self-seed prolifically in gardens in the UK and temperate parts of North America and Australia. It is naturalized in parts of the northeastern United States and eastern Canada; this is not the same as being formally listed as invasive. Remove seed heads where spread is unwanted.

• Wild columbine (Aquilegia canadensis)

  Usually has red-and-yellow flowers with relatively straight spurs; common columbine usually has violet-blue flowers with distinctly hooked spurs.

• Rocky Mountain columbine (Aquilegia coerulea)

  Typically has more outward-facing blue-and-white flowers with long, relatively straight spurs, rather than the shorter hooked spurs and nodding flowers of common columbine.

• Meadow-rue (Thalictrum species)

  Some have similarly divided, rounded foliage, but their flowers are small and fluffy or starry, without columbine's distinctive bonnet shape and spurs.

Granny's bonnet refers to the flower's old-fashioned bonnet shape, while vulgaris means common.

Propagation. Sow fresh seed in pots outdoors and keep it moist; germination can be irregular, and a period of winter cold may help. Transplant seedlings while small. Garden forms cross readily, so seedlings may differ from their parents; division is possible but established plants resent root disturbance.

Accepted botanical name

Aquilegia vulgaris

In the US and Canada

Introduced in the lower 48 states.

Native range

Albania, Austria, Baltic States, Belarus, Belgium, Bulgaria, Central European Rus, Corse, Czechoslovakia, France, Germany and Great Britain.

Measured

Soil pH 7 to 7.5. Average height 45 cm.

Sources: GBIF (CC BY 4.0), USDA PLANTS and Trefle (CC BY 4.0). The care and design notes are LandscapeGPT's own.