Dormancy

    Prostrate Knotweed

    Polygonum aviculare

    prostrate knotweed

    Prostrate knotweed growth habit (Robert Videki, Bugwood.org)

    prostrate knotweed

    Prostrate knotweed flower (Bruce Ackley, The Ohio State University, Bugwood.org)

     

    Description

    • low-growing plant with wiry stems that radiate out from a central point and grow up to 2 feet in length
    • small leaves join the stems at enlarged “joints” that are covered in a papery sheath
    • tiny white or pink flowers have five petals and green centers

    Location

    • commonly grows in planting beds but can sometimes be found in lawn areas

    Life Cycle

    • summer annual with seedling germination in early spring; seedling growth is slow
    • flowers and seeds are produced mid-spring to fall frost

    IPM Recommendations

    • Hand-pull plants prior to seed maturation.
    • Prostrate knotweed thrives in compacted soil; avoid or reduce soil compaction by aeration or preventative methods.
    • Apply a mulch layer 3 inches deep on planting beds to reduce seed germination.
    • Apply an appropriate pre-emergent herbicide prior to seed germination or post-emergent herbicide to young seedlings (less than 3 inches wide).