Carthusian pink

Sun

Full sun; flowering and stem strength decline in shade.

Water

Low to moderate. Water regularly while establishing, then during prolonged dry spells; avoid persistently damp soil.

Soil

Well-drained, lean to moderately fertile soil, preferably neutral to alkaline. Tolerates sandy, stony and chalky ground; struggles in wet clay.

Height

1.5-2.5 ft (0.45-0.75 m)

Spread

0.5-1 ft (0.15-0.3 m)

Flowers

Early to late summer; deep pink to magenta flowers in tight clusters at the tips of slender stems.

Foliage

Narrow, green, grass-like leaves form a low tuft. Basal foliage can persist through mild winters but may die back in colder climates.

Growth

Moderate

Care needed

Low

• Pollinators
• Deer resistant
• Drought tolerant
• Cold hardy
• Wildlife
• Low allergen

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

Difficulty

Easy

Toughness

Very 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

Mildly toxic: may upset a stomach

Invasive in

the US

In the garden

Spreads vigorously: plan to contain it.

Growth rate

Moderate

• Plant with the crown at soil level in a sunny position with sharp drainage.
• Water new plants when the root zone begins to dry; established clumps need little supplementary watering.
• Avoid rich manure and heavy feeding, which encourage soft, floppy growth.
• Use a light gravel mulch rather than piling organic mulch around the crown.
• Divide congested or thinning clumps in spring, keeping well-rooted outer sections.

Pruning. Cut spent flower stems back to the basal leaves during summer to limit seeding and sometimes encourage further flowers. Remove dead stems and damaged foliage in late winter or early spring without cutting into the crown.

Early spring

Remove dead foliage and check that winter debris has not buried the crown.

Spring

Plant nursery-grown plants or divide established clumps; water until rooted.

Late spring

Weed around the low leaf tufts before flower stems rise.

Summer

Deadhead spent stems and water during prolonged drought.

Late summer

Where local regulations allow, collect ripe seed as capsules turn brown, or remove heads before seeds escape.

Autumn

Remove unwanted seedlings and keep fallen leaves away from the crowns.

• Repeat small groups through a sunny gravel garden for bright flowers above a low, open planting.
• Weave among fine ornamental grasses to create a light, meadow-like effect.
• Plant near the front of a perennial border, where its transparent stems will not hide neighbouring plants.
• Combine with blue catmint, white yarrow and purple salvias for a long-flowering, drought-tolerant border.

Garden styles it suits: Cottage garden, Dry gravel garden, New perennial (prairie), Pollinator garden, Low-maintenance and Wildflower.

Plant it with: Catmint, Meadow sage, Yarrow, Blue fescue, Small scabious and Creeping thyme.

Wildlife: Flowers provide nectar for butterflies and other long-tongued insects. It is native to parts of Europe, not to North America or Australia; use locally native alternatives where restoring native grassland is the goal.

• Crown or root rot in wet ground: improve drainage or move plants to a raised, gritty bed; discard badly rotted clumps.
• Rust, seen as orange-brown pustules on leaves: remove affected foliage, improve air circulation and avoid wetting the leaves when watering.
• Slugs and snails damaging young growth: inspect after dark, remove them and clear damp hiding places near the crown.
• Floppy stems or poor flowering: provide more sun and stop high-nitrogen feeding; support temporarily with twiggy stems if needed.

Dianthus plants can cause mild vomiting or diarrhoea in cats and dogs if eaten, and contact may irritate skin. Sap may also irritate sensitive human skin; do not treat this ornamental species as food. It is not known to be toxic to horses, but species-specific evidence is limited.

Where it spreads. Listed as a restricted invasive plant in Wisconsin, USA, where planting and movement are regulated. It can self-seed into open, dry grassland; check local restrictions before planting and remove seed heads where escape is a concern.

• Sweet William (Dianthus barbatus)

  Sweet William has broader leaves and much larger, flatter flower heads on sturdier, leafier stems.

• Deptford pink (Dianthus armeria)

  Deptford pink is noticeably hairy and usually has smaller, white-speckled pink flowers with long, narrow green bracts;

• Maiden pink (Dianthus deltoides)

  Maiden pink makes a lower, spreading mat with flowers borne singly or in loose groups rather than compact terminal clusters.

The epithet carthusianorum and the common name refer to the Carthusian religious order, traditionally associated with growing the plant in monastery gardens.

Propagation. Sow seed in spring in a free-draining seed mix, covering lightly, or divide established clumps in spring. Flowering from seed may begin in the first year but often starts in the second; do not propagate where local invasive-plant rules prohibit it.

Accepted botanical name

Dianthus carthusianorum

In the US and Canada

Introduced in the lower 48 states.

Native range

Albania, Austria, Belarus, Belgium, Bulgaria, Czechoslovakia, France, Germany, Hungary, Italy, Poland and Romania.

Measured

Soil pH 7 to 7.5. Average height 44 cm.

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