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Ceratophyllum demersum

hornwort

C. demersum is a submerged perennial with forked, dark green leaves, with tiny flowers in summer

Other common names
cedar moss
coon tail
see morefish blankets
horn weed
morass weed
rigid hornwort

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Size
Ultimate height
Up to 10cm
Time to ultimate height
5–10 years
Ultimate spread
1–1.5 metres
Growing conditions
Clay
Loam
Moisture
Poorly–drained
pH
Acid, Alkaline, Neutral
Colour & scent
StemFlowerFoliageFruit
Spring Green
Summer White Green
Autumn Green
Winter
Position
  • Full shade
  • Full sun
  • Partial shade
Aspect

West–facing or South–facing or North–facing or East–facing

Exposure
Exposed or Sheltered
Hardiness
H4
Botanical details
Family
Ceratophyllaceae
Native to the UK
No
Foliage
Deciduous
Habit
Submerged
Genus

Ceratophyllum are submerged aquatic perennials with whorled, linear leaves more crowded near the stem apex, and tiny insignificant flowers in the leaf axils in summer

Name status

Correct

Plant range
EC Eur. to Afr.

How to grow

Cultivation

Grow in water 30-90cm deep in full sun to shade. Plants float freely. Plants die back in winter but modified stem buds, turions, overwinter in bottom mud and re-grow in spring

Propagation

Propagate by stem cuttings and allow to float in water

Suggested planting locations and garden types
  • Low Maintenance
Pruning

No pruning required

Pests

Generally pest free

Diseases

Generally disease free

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