Seasonal Wild Flowers

Sea Knotgrass

Polygonum maritimum

Polygonaceae

July to September

It is found patchily on the coasts of the South and the far

Southwest,

See the BSBI distribution map for Sea Knotgrass

It grows on sandy, shingle and shell seashores above

the highest tide line.

Sea Knotgrass is a native, prostrate, greyish, perennial

herb, growing up to 40cm.

Flowers (1-4 together) are at the end of the leafy spike.

Tepals (5) are pink, greenish or white.

Leaves are up to 15mm, slightly leathery and with down

turned margins

They have long (up to 1cm) sheaths, which are silvery

with 8-12 branched veins.

Fruits are brown nuts, which protrude above the dead

flowers (not shown here. See similar on Ray's Knotgrass

- June).

Stems are stout and woody at the base.

Previous page: Sea-heath
Next page: Sea Mayweed

Sea Knotgrass on a sandy beach in

West Cornwall

Groups of flowers on flower spike

4 tepals, yellow stamens

Veined, silvery flower sheaths

Leaves with recurved margins

Habit - sprawling over small rocks