Carthusian pink

Carthusian pink: how do you recognise it?

Habit

Narrow, upright plant 50 cm tall and 20 cm wide, with a low tuft of leaves and slender flowering stems.

Leaves

Narrow and grass-like, green, in a small tuft at the base and in pairs along the stem.

Flower

Dense heads of small flowers with five toothed petals, bright pink to magenta, surrounded by brown, papery bracts.

Fruit

Small capsules with black seeds that drop out easily.

Lifespan

Often short-lived, but it keeps going by self-seeding.

Flowering: June–August · Sowing: March–May · Plants: March–April and September–October · Pruning: March and August

Why grow it?

• Vivid pink dots of colour from June to August, floating prettily among grasses.
• Butterflies and bees visit the flowers; butterflies in particular reach the nectar easily with their long tongues.
• Drought tolerant: ideal for a gravel garden, rock garden or dry bank.
• Takes up little room and fits into small gaps between other plants.
• Self-seeds and so stays in the garden for years.

Carthusian pink: where does it grow best?

• Full sun: in shade it flowers poorly and the stems flop.
• Poor, free-draining sandy or loamy soil, neutral to chalky.
• Dry: wet soil, especially in winter, makes it rot.
• Plant 20 cm apart, in small groups among grasses and other dry-garden plants.

Light

Sun

Soil type

Sand or loam

Acidity

Neutral or chalky

Moisture

Dry

Size

0.5 m tall, 0.2 m wide

Hardiness

Hardy (to -35 °C)

Goes well with

• Feather grass: Fine, swaying stems with the pink heads floating between them.
• Wild thyme: A low, fragrant carpet at its feet, on the same dry soil.
• Harebell: Fine blue bells next to the vivid pink.
• Stonecrop: Yellow stars in June on poor, dry spots.
• Catmint: Clouds of blue that soften the bright colour.

Carthusian pink: when and how to plant it?

Plant in March–April and September–October.

1. Plant in March–April or in September–October.
2. Loosen the soil and on heavier ground mix in some coarse sand or gravel.
3. Do not put compost or fertiliser in the planting hole: poor soil suits it better.
4. Set the young plants at the same depth as in their pots, no deeper, 20 cm apart.
5. Water straight away and again in dry spells for the first few weeks.
6. A thin layer of gravel around the base keeps the neck of the plant dry.

Care

Water

Water young plants only in dry spells; after that it is no longer needed.

Feeding

Not needed: on rich soil the stems become floppy.

Spent flowers

Cut off some of the faded stems for a longer display and leave a few to self-seed.

Seedlings

Leave young seedlings where they are or move them in spring with a small root ball to a spot of your choice.

Lime

On acid soil a handful of lime in spring helps.

Tip: Let a few flowering stems set seed every year: the plant itself often lives only a few years, but this way new plants keep appearing.

Carthusian pink: when to prune it?

Pruning months: March and August.

When: After the main flowering, in August, and in March to clear away the old stems.

How:

• In August cut faded stems back to just above the leaf tuft; leave a few if you want seedlings.
• In March cut away the old, dry stems, but leave the green tuft of leaves.
• Never cut into the green leaves at the base.

Pruning: when and how · Pruning calendar and basic rules

Propagation

Seed

Indoors in March–April or outdoors in April–May: sow thinly, barely cover the seed and keep the soil slightly moist. It germinates within a few weeks; seedlings often flower in their second year.

Self-seeding

Let the capsules ripen on the plant; you can move the seedlings in spring with a small root ball.

Division

Older clumps can be carefully divided in spring, but young seedlings establish better.

Carthusian pink: how does it get through the winter?

Hardy to −35 °C.

• Very hardy, to about −35 °C: frost is no problem in Belgium.
• Wet soil in winter is dangerous, though: the clump rots if water stands around it.
• The leaf tuft often stays green in winter.
• In a pot or trough: keep it dry, for example under a canopy, in free-draining compost.

Diseases and pests

• Rotting: The clump turns brown and soft after a wet winter. Plant it in a drier spot, with gravel around the base.
• Short life: After a few years the parent plant dies. Always let some seed ripen for new plants.
• Slugs: They eat young plants and seedlings. Pick them off in the evening.
• Aphids: On the flower buds in June. Spray off with water.

Through the year

• March: Cut away old stems. Sow indoors. Plant.
• April: Sow outdoors. Plant. Move seedlings.
• May: Sow outdoors. Watch for slugs.
• June: Flowering begins.
• July: Full bloom. Butterflies on the flowers.
• August: Cut off some of the faded stems. Let seed ripen.
• September: Collect seed or let it fall. Plant.
• October: Plant.
• December: Rest. The leaf tuft stays green.

Good for wildlife

Bees

Nectar and pollen for honeybees and wild bees.

Butterflies

Nectar for butterflies.

Did you know?

• The name refers to the Carthusians, the monks of the Grande Chartreuse monastery in France.
• Under each flower head sit brown, papery bracts: a good way to recognise it.
• Pinks are pollinated mainly by butterflies and moths, whose long tongues reach deep into the flower tube.