Not the plant you're looking for? Search over 300,000 plants

Aquatic

Potamogeton pectinatus

fennel pondweed

A submerged perennial with thread-like submerged leaves and insignificant submerged flowers in summer; useful oxygenator

Other common names

duck grass
duck moss
see morepotato moss

Save to My plants

Ultimate height

Up to 10cm

Time to ultimate height

5–10 years

Ultimate spread

0.5–1 metres

Loam

Sand

Moisture

Poorly–drained

pH

Acid, Alkaline, Neutral

	Stem	Flower	Foliage	Fruit
Spring
Summer
Autumn
Winter

Full sun
Partial shade

Aspect

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

Exposure

Exposed or Sheltered

Hardiness
Hardiness ratings
All ratings refer to the UK growing conditions unless otherwise stated. Minimum temperature ranges (in degrees C) are shown in brackets
H1a: under glass all year (>15C)
H1b: can be grown outside in the summer (10 - 15)
H1c: can be grown outside in the summer (5 - 10)
H2: tolerant of low temperatures, but not surviving being frozen (1 to 5)
H3: hardy in coastal and relatively mild parts of the UK (-5 to 1)
H4: hardy through most of the UK (-10 to -5)
H5: hardy in most places throughout the UK even in severe winters (-15 to -10)
H6: hardy in all of UK and northern Europe (-20 to -15)
H7: hardy in the severest European continental climates (< -20)

Botanical details

Family: Potamogetonaceae
Native to GB / Ireland: Yes
Foliage: Deciduous
Habit: Submerged
Genus: Potamogeton can be marginal or deep water aquatic perennials, with translucent submerged and leathery floating leaves, and small spikes of inconspicuous flowers held below or just above water level
Name status: Correct

How to grow

Cultivation

Grow in baskets of sandy loam in the bottom mud of the pond, in full sun or partial shade. See pond plants for further advice

Propagation

Propagate by stem cuttings from mid spring to early summer

Suggested planting locations and garden types

Low Maintenance

Pruning

Thin on a regular basis to keep in check

Pests

Generally pest-free

Diseases

Generally disease-free

Get involved

The Royal Horticultural Society is the UK’s leading gardening charity. We aim to enrich everyone’s life through plants, and make the UK a greener and more beautiful place.