Caucasian scabious

Sun

Full sun; light afternoon shade can help in warmer gardens.

Water

Moderate; keep evenly moist while establishing, then water during prolonged dry spells. Avoid persistently wet soil.

Soil

Well-drained, moderately fertile soil, preferably neutral to alkaline. Improve heavy clay drainage before planting.

Height

1.5-2.5 ft (0.45-0.75 m)

Spread

1-1.5 ft (0.3-0.45 m)

Flowers

Early summer to early autumn with deadheading; usually lavender-blue to violet-blue, with white and paler blue cultivated forms.

Foliage

Grey-green to green leaves form a basal clump; basal leaves are narrow and mostly undivided, while upper stem leaves are often divided.

Growth

Moderate

Care needed

Medium

• Pollinators
• Deer resistant
• Cold hardy
• Low allergen

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

Difficulty

Moderate

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

   1.3 ft (0.4 m)

3. After 2 years

   1.6 ft (0.5 m)

4. After 3 years

   2 ft (0.6 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

Growth rate

Moderate

• Plant with the crown at soil level in a sunny position with good drainage.
• Water deeply during dry spells, allowing the surface soil to dry between waterings.
• Apply a thin layer of compost in spring; avoid heavy feeding, which encourages floppy growth.
• Keep mulch clear of the crown, especially through wet winters.
• Use discreet twiggy supports if flower stems lean in exposed sites.
• Divide congested or weakening clumps in spring, usually every three or four years.

Pruning. Remove faded flower stems back to a leaf or side shoot throughout summer to encourage more blooms. Cut dead stems and foliage back to the crown in late autumn or early spring.

Early spring

Remove dead growth and check that the crown has not become buried under mulch.

Spring

Plant new plants or divide established clumps as fresh growth begins.

Late spring

Add discreet supports before flower stems become tall.

Summer

Deadhead regularly and water deeply during prolonged dry weather.

Early autumn

Leave a few seedheads if you want seed; named varieties may not come true.

Late autumn

Clear collapsed foliage and keep the crown free of wet debris.

• Plant in small groups near the front or middle of a sunny border, where the flowers can rise above lower foliage.
• Combine with roses, catmint and hardy geraniums for a soft blue-and-pink cottage border.
• Thread through low ornamental grasses to give an airy, informal effect.
• Use in a sunny cutting bed for long-stemmed summer flowers.

Garden styles it suits: Cottage garden, English country, Romantic rose garden, Pollinator garden, Blues and silvers and Pastel border.

Plant it with: Catmint, Hardy geranium, Roses, Garden sage, Yarrow and Lamb's ear.

Wildlife: Open flowers attract bees, butterflies and other nectar-feeding insects.

• Crown or root rot in wet soil: improve drainage, keep mulch away from the crown and replace badly rotted plants.
• Powdery mildew in crowded or stressed plants: increase airflow, water during drought and remove badly affected foliage.
• Slugs and snails damaging young shoots: inspect emerging growth and use barriers, hand removal or locally approved iron phosphate bait.
• Flopping stems or poor flowering: provide more sun, avoid nitrogen-rich feeding and support stems before they lean.

Not known to be toxic to people, cats, dogs or horses. No part is recognized as a significant poisoning hazard, but it is an ornamental plant rather than a food plant.

• Small scabious (Scabiosa columbaria)

  Usually has smaller, less broadly frilled flowerheads and more finely divided foliage; Caucasian scabious has conspicuously large outer florets.

• Sweet scabious (Scabiosa atropurpurea)

  Usually grown as an annual or short-lived perennial, with smaller, more domed flowerheads in colours including burgundy, pink and white; Caucasian scabious has broad, flatter heads and a persistent basal clump.

The epithet caucasica refers to the Caucasus region, while pincushion flower describes the head's cushion-like centre with projecting floral parts.

Propagation. Divide healthy clumps in spring. Sow seed in spring for variable offspring; use division or basal cuttings in spring to preserve the characteristics of named varieties.

Accepted botanical name

Lomelosia caucasica

Native range

Iran, North Caucasus, Transcaucasus and Turkey.

Measured

Average height 48 cm.

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