Koenigia alaskana (synonym Aconogonon alaskanum, Persicaria alpina) is an Asian and North American species of flowering plant in the buckwheat family known by the common names Alaska wild-rhubarb and alpine knotweed.

[2] This herbaceous or semi-evergreen[2] perennial grows up to 2 meters (almost 7 feet) tall, with a woody root and lanceolate leaves.

The abundant flowers are white, cream or pale green, borne in plumes in midsummer.

[2] Koenigia alaskana is native to Alaska, the Yukon, and Magadan Oblast in the Russian Far East.

Under the name Persicaria alpina it has received the Royal Horticultural Society's Award of Garden Merit.