Overview

Houstonia caerulea L. is a low-growing, mat-forming alpine rockery in the genus Houstonia, part of the Rubiaceae family, with opposite, ovate to lanceolate leaves foliage. Houstonia caerulea L. grows best in full sun, and tolerates loam soils and neutral pH. Its UK hardiness is rated H4. Suggested uses include ground cover, rock gardens and woodland edges.

About

Houstonia caerulea L. (bluets) is a low-growing, mat-forming alpine rockery plant from the Rubiaceae family. It features opposite, ovate to lanceolate leaves and thrives in full sun on a south-facing, sheltered aspect. Best grown in moist, neutral loam soil, it is hardy to UK zone H4. This cultivar is suitable for ground cover, rock gardens, and woodland edges, with interest in spring and summer. For cultivation, plant in well-drained soil and water during establishment. Propagation is by seed or division.

Growing conditions

Best soil and position for Houstonia

Sunlight

Full sun

Soil type

Loam

Soil pH

Neutral

Soil moisture

Moist

Aspect

South-facing

Exposure

Sheltered

UK hardiness

H4

Plant details

Houstonia caerulea L. size, habit and characteristics

Plant type

Alpine Rockery

Habit

Low-growing, mat-forming

Foliage

Opposite, ovate to lanceolate leaves

Suggested uses

Ground cover, rock gardens, woodland edges

Care notes

Pruning and caring for Houstonia caerulea L.

Propagation

Seed, division

Pest resistance

Resistant to deer and rabbits

Disease resistance

Susceptible to powdery mildew

Frequently asked questions