Overview
Costus spectabilis is a clump forming conservatory greenhouse in the genus Costus, part of the Costaceae family, with evergreen foliage. Costus spectabilis grows best in full sun, and tolerates loam soils and neutral pH. Its UK hardiness is rated H1a. Suggested uses include conservatory and greenhouse.
About
Costus spectabilis, commonly known as the yellow trumpet, or yellow bell, is an African species of herb; low and perennial, it is found from Sierra Leone to Sudan to as far south as Angola and Zimbabwe. Field observations — Completely leafless flowering specimens have been collected in May – June and October – De- cember. In the garden it prefers full sun and loam soil. In UK gardens it needs tropical warmth and glass protection in the UK (RHS H1a). Suggested uses include conservatory and greenhouse. It tolerates neutral soils, moist but well-drained conditions and south-facing aspects. Plant in well-drained soil in a suitable position. Water during establishment.
Wikipedia contributors, CC BY-SA 4.0 — Costus spectabilis
Growing conditions
Best soil and position for Costus
- Sunlight
- Full sun
- Soil type
- Loam
- Soil pH
- Neutral
- Soil moisture
- Moist but well-drained
- Aspect
- South-facing
- Exposure
- Sheltered
- UK hardiness
- H1a
Plant details
Costus spectabilis size, habit and characteristics
- Plant type
- Conservatory Greenhouse
- Habit
- Clump forming
- Foliage
- Evergreen
- Suggested uses
- Conservatory and greenhouse
Care notes
Pruning and caring for Costus spectabilis
- Propagation
- Seed, division in spring
- Pest resistance
- Susceptible to glasshouse red spider mite under glass
- Disease resistance
- Generally disease-free
Frequently asked questions
Where is the best place to plant Costus spectabilis?
Costus spectabilis prefers full sun. It suits sheltered positions.
What soil does Costus spectabilis need?
Costus spectabilis grows best in loam soil. It prefers neutral soil. Aim for soil that stays moist but well-drained.
Is Costus spectabilis hardy in the UK?
Costus spectabilis has an RHS hardiness rating of H1a, meaning it needs tropical warmth above 15°C and must be grown under glass in the UK.
How do I propagate Costus spectabilis?
Seed, division in spring.
