Plumbago
Ceratostigma plumbaginoides · Plumbaginaceae
📷 Denis.prévôt · CC BY-SA 3.0
The gardener's calendar
Plumbago is in full bloom: enjoy it, watch watering in hot weather and let spent flowers feed pollinators before pruning.
ID card
- Foliage
- Deciduous, bronzed in autumn
- Flowering
- August to October, cobalt blue flowers
- Adult height
- 30 to 40 cm
- Hardiness
- Hardy down to -15°C
- Growth
- Moderate to fast
- Origin
- Himalayas and China
- Soil type
- Well-drained, light, rather poor
✓ Taxonomy verifiedSource: AI estimate · hardiness: reliability high.
Expert tips
The key tip
Plant in organic-rich soil, partial shade to light shade. Water regularly in spring-summer, then reduce in autumn but keep soil fresh.
The common mistake
Placing it in scorching full sun where it yellows and flowers poorly, or too much shade where it stretches awkwardly toward light.
The pro's trick
Sow in March in a cold frame: germinates in 3-4 weeks, and young plants divided in April give you dense clumps by August.
Seasonal watch
August-September: flowering and striking electric blue foliage.
Care
Light exposure
Ceratostigma thrives in part shade or partial sun. It tolerates direct sunlight in temperate climates, but prefers protection from the hottest hours in very sunny regions. Too much shade reduces flowering.
Watering
Water regularly during growth, without excess. The soil should dry slightly between waterings. Reduce watering in autumn and winter. Stagnant moisture causes root rot.
Soil
Plant ceratostigma in well-drained, light, rather poor soil. Soil that is too rich promotes foliage at the expense of flowers. Improve heavy soil with sand or gravel.
Pruning and maintenance
Cut back the plant in late winter or early spring, before growth resumes. This pruning encourages a compact form and better flowering. Remove dead or damaged stems.
Fertilizing
A light application of balanced fertilizer in spring is sufficient. Avoid excess nitrogen, which weakens the plant. If the soil is naturally poor, moderate fertilizer in early summer supports flowering.
Diseases and pests
Ceratostigma is very robust. Watch for powdery mildew in humid, stagnant conditions: ensure good air circulation and avoid spraying foliage. Spider mites may appear in dry conditions: mist with soft water if necessary.
Did you know?
Ceratostigma was long known by the name Plumbago larpentae and its genus name "ceratostigma" refers to its stigmas (female parts of the flower) equipped with small horns. Its intensely cobalt blue flowers are extraordinarily luminous in late summer and attract pollinating insects late into the season.
Where to buy it
Plant in spring or early autumn, avoiding spells of intense heat. Pick a plant with healthy foliage and roots that are not exposed. Best time: March, April, May, September.
Add this plant to my garden →Plants from the same family
- Sea thriftArmeria maritima
- German staticeGoniolimon tataricum
- Chinese-plumbagoCeratostigma willmottianum
- Ceratostigma griffithiiCeratostigma griffithii
- Armeria arenariaArmeria arenaria
- Limoniastrum monopetalumLimoniastrum monopetalum
Tips generated and checked by Viridia — adapt them to your local climate.