Fennel Pondweed - Potamogeton pectinatus


    The grass-like Fennel Pondweed is a submerged plant that grows from a creeping rhizome. The multiple long stems often form masses at the water surface. Underwater stands may look like grassy meadows. The stems are slender and flexible. They are only about an eighth of an inch thick and are usually several feet long. The stems have many branches, and may be green, brown, or reddish. Fennel Pondweed leaves are very narrow; not much wider than the slender stems. The leaves are usually several inches long. They taper to narrow points. The flowers of Fennel Pondweed are on spikes. The flowers are very tiny and greenish, and grow in several whorls along the flower spike.

    Similar Species

    other narrow-leaved pondweeds

    Identification difficulty
    Recording advice

    The County Recorder has asked for a specimen of this plant to be retained for verification


    Fennel Pondweed grows in fresh, brackish, and saline waters. It is found in ponds, lakes, rivers and canals.

    When to see it

    Flowers June to September.

    Life History


    UK Status

    Widespread in England, predominantly coastal in Scotland and Wales.

    VC55 Status

    Fairly frequent in Leicestershire and Rutland. In the 1979 Flora survey of Leicestershire it was found in 67 of the 617 tetrads.

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    Leicestershire & Rutland Map

    MAP KEY:

    Yellow squares = NBN records (all known data)
    Coloured circles = NatureSpot records: 2020+ | 2015-2019 | pre-2015

    UK Map