Amorphophallus konjac
konjaku
A tuberous perennial producing a single flower in summer consisting of a shiny, red-purple spathe and tall, paddle-like, brown spadix. It has an unpleasant smell to attract pollinating flies.After the flower has faded a single, highly divided leaf appears with bright green leaflets and a stout, olive-green stem with white markings
Synonyms
Amorphophallus rivieri
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Size
Ultimate height
1–1.5 metresTime to ultimate height
5–10 yearsUltimate spread
1–1.5 metresGrowing conditions
Moisture
Moist but well–drainedpH
Acid, Alkaline, NeutralColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | ||||
|---|---|---|---|---|
| Summer | Green White | Brown Purple | Green | |
| Autumn | Green White | Green | ||
| Winter |
Position
- Partial shade
Aspect
West–facing or East–facing
Exposure
Sheltered Hardiness
H1BBotanical details
- Family
- Araceae
- Native to GB / Ireland
- No
- Foliage
- Deciduous
- Habit
- Columnar upright
- Potentially harmful
- Harmful if eaten, skin/eye irritant. Wear gloves and other protective equipment when handling Pets: Harmful if eaten, skin/eye irritant - see the HTA guide to potentially harmful plants for further information and useful contact numbers
- Genus
Amorphophallus are perennials with corm-like rhizomes and huge, deeply-lobed leaves. The flowers are composed of a purple-red to greenish-white spathe, often unpleasantly-scented, and a central spadix
- Name status
Correct
- Plant range
- Indonesia to Japan
How to grow
Cultivation
Plant dormant tubers 10cm deep in late winter or early spring in a large container of peat-free, loam-based potting compost. Grow in filtered light, water and feed while in active growth, and overwinter in warm, barely moist conditions
Propagation
Separate offsets when dormant, or propagate by seed sown in heat in autumn or early spring
Suggested planting locations and garden types
- Patio and container plants
- Sub-tropical
Pruning
No pruning required
Pests
Generally pest-free
Diseases
Generally disease-free
Get involved
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